kvitt/SPEC.md

Kvitt: specification

Version 0.40 (2026-10-24). Schema version 4. Sync protocol version 1. Push payload version 1.

This file is the single source of truth for Kvitt. It is written for implementation agents that have no other context. If code, a plan or CLAUDE.md disagrees with this file, this file is right. Words in code are literal identifiers, paths, enum values or error codes and must be used exactly as written. Anything not decided here is listed in §12 as TODO(spec); do not invent a value for it.

Conventions used throughout:

• "Owner" is Jacob, the admin user. "Partner" is the other user. "User" is either of the two.
• "Öre" is 1/100 SEK. All money is an integer number of öre.
• "bp" is basis points. 10000 bp is 100 %.
• Timestamps are RFC 3339 UTC strings in exactly this form: 2026-10-17T06:00:00.000Z (millisecond precision, literal Z). This form sorts correctly as a string.
• Dates without time are ISO 8601 YYYY-MM-DD. Months ("periods") are YYYY-MM. ISO weeks are YYYY-Www with the ISO week-numbering year (week starts Monday).
• Ids are UUIDv7, lowercase, hyphenated, 36 characters, stored and sent as strings.
• JSON keys are snake_case. Enum values are lowercase snake_case strings.
• "Must", "must not" and "may" are binding.

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1. Overview & goals

Kvitt is a shared-expense app for one household of exactly two people living in Sweden: the owner and his spouse. It replaces Splitwise for them. It tracks who paid for what, who owes whom, and how the household spends money over time.

It consists of:

• A native Android app (Kotlin, Jetpack Compose) on two Samsung phones (Galaxy S26 and Galaxy S26+, Android 16). The app keeps a full copy of the household's data in a local Room database and works fully offline for expenses and settlements.
• A small Rust server (axum, SQLite) in Docker on a Raspberry Pi 3 at the owner's home, reachable at https://<KVITT_PUBLIC_HOST> (the default HTTPS port 443, D-124), where KVITT_PUBLIC_HOST is the Kvitt host name (KVITT_PUBLIC_HOST, owner-chosen, recorded in HANDOFF), through the owner's Nginx Proxy Manager on the Home Assistant Pi (D-120). The server stores the authoritative copy, syncs the phones, creates recurring expenses, sends push notifications, keeps an audit log and hosts the APK for in-app updates.
• A web client (D-129, §15): a React single-page app built into the server image and served by the server under /app/, for a browser on the owner's or the partner's computer. It has the app's features except the phone-only ones (pairing flow, push, offline use, in-app update), plus search, CSV export and keyboard shortcuts. It is online only.
• Card purchases (D-158, §9.12, FR-22): each user may connect their own payment card (at first the SJ Prio Mastercard) through the account-information service Enable Banking; the server reads that card's purchases and the card holder, and only the card holder, turns them into ordinary household expenses with a few taps. Read only: Kvitt never pays or moves money.

Goals for v1:

1. G-1 Correct money. Balances are exact to the öre and computed identically on phone and server, guaranteed by shared test vectors.
2. G-2 Offline first. Creating, editing and deleting expenses and settlements never waits for the network. Two weeks offline followed by a sync loses nothing.
3. G-3 Flexible splitting. Per-account default ratios (50/50 to start, configurable such as 60/40), custom ratios, exact amounts, or 100 % on one person.
4. G-4 Clear settling. One global balance, a per-account breakdown, and a settle-up flow that proposes how a payment is spread over accounts.
5. G-5 Insight. Monthly and weekly spending by category and by account, computed on the phone; averages, trends and a two-month forecast computed on the server (D-133).
6. G-6 Trust. Every change to an expense or settlement is visible as a timeline of who did what.
7. G-7 Low-maintenance hosting. One docker-compose stack on a 1 GB Raspberry Pi, nightly off-site backups, no cloud services except Firebase Cloud Messaging, Google Drive for backups and, for card purchases only, the account-information service Enable Banking (D-159).
8. G-8 Bilingual. Every user-visible string exists in Swedish and English. The phone's locale decides: Swedish when the device language is Swedish, English otherwise.
9. G-9 History. Six years of Splitwise history can be imported once, repeatably without duplicates.

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2. Non-goals

Not in v1. Agents must not build any of these, even partially:

• Receipt photos or receipt scanning. Profile pictures are the only file upload.
• Any card, bank, Spendwise or other financial-institution integration. Revised by D-158: reading the purchases of the users' own payment cards through Enable Banking (account information only, §9.12, FR-22) is in scope. Still out: payments or transfers of any kind, bank accounts other than the connected cards, Spendwise, and any other provider than those in the card catalogue (E-36).
• Multiple currencies or exchange rates. All amounts are SEK. (The importer has a one-off conversion option, §4 FR-17.)
• Joint accounts, shared cards or "paid from the shared pot" as a payer. The payer is always one of the two users.
• More than two users, more than one household, user deletion.
• Passwords, password reset, email, SMS, OAuth sign-in.
• Play Store distribution.
• CSV or any other export, except the web client's CSV export of a filtered expense list (D-129, §15.7).
• A web client. The only HTML the server serves is the invite landing page (§4 FR-2). Revised by D-129: the web client of §15 is in scope; it is not a progressive web app and has no offline use. The server serves HTML for the invite landing page (§4 FR-2) and the web client under /app/ (D-132).
• Server-side reporting beyond the advanced analytics of D-133 (§15.8): S-11 and S-12 stay computed on the phone.
• Debt simplification (meaningless with two users) and netting several accounts in opposite directions inside one settlement.
• Editing accounts, categories, recurring templates, profiles or invites while offline.
• Tablet, foldable or landscape-specific layouts of the Android app. Portrait phone only; landscape must not crash. (The web client is designed for the desktop, §15.1.)
• Widgets, Wear OS, iOS.
• In-app language picker in the Android app. The phone locale decides. (The web client has a language choice, §15.3.)
• Comments or chat on expenses.

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3. Users & core user stories

3.1 Roles

Role	Who	Count	Extra rights
admin	The owner	exactly 1	Creates invites (partner and device), cancels invites, revokes any device
member	The partner	0 or 1	Revokes own devices other than the one in use

Everything else (expenses, settlements, accounts, categories, recurring templates) is open to both users with identical rights. Either user may edit or delete anything the other created. Each user edits only their own display name and picture.

A user has one or more devices. v1 expects one phone each, but the model allows any number of devices per user without change.

3.2 User stories

• US-1 As the owner I set up the server once from the command line and pair my phone with a one-time code.
• US-2 As the owner I invite my partner with a link; my partner installs the app from the link, picks a name and a picture, and is paired.
• US-3 As a user I add an expense in a few taps: amount, description, category, account; the split defaults to the account's ratio and the payer defaults to me.
• US-4 As a user I record an expense my partner paid, so they do not have to.
• US-5 As a user I split an expense differently: a custom ratio, exact amounts, or the whole amount on one of us.
• US-6 As a user I see one number saying who owes whom overall, and the same per account.
• US-7 As a user I settle up: I enter what I paid my partner, the app proposes which accounts it settles (oldest first), I adjust and confirm.
• US-8 As a user I settle one account from that account's screen.
• US-9 As a user I create expense accounts ("Vardag", "Huset", "Japan 2027"), give each a default ratio, and archive them when done.
• US-10 As a user I set up a recurring expense (rent, streaming) that appears automatically each month.
• US-11 As a user I see how much we spent per month or week, by category or by account, as a household total or as my share.
• US-12 As a user I add and edit expenses on a plane or abroad without a connection, and everything syncs when I am back.
• US-13 As a user I get a notification when my partner adds, changes or deletes something, and I can see in the expense who changed what.
• US-14 As a user I am told when a new app version exists and install it from inside the app.
• US-15 As the owner I import our Splitwise history once.
• US-16 As the owner I can restore everything from a backup if the Pi dies.
• US-17 As the owner I can remove a lost phone's access.
• US-18 As a user I connect my own payment card with BankID once and then see my card purchases in Kvitt, updated by themselves, without typing them (D-158).
• US-19 As a user I turn a card purchase into a household expense, or link it to the expense my partner already entered, in one or two taps, from the Kortköp tab or from an account (D-158).

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4. Functional requirements (v1)

Each requirement has acceptance criteria (AC). An AC is satisfied only when a test (unit, integration, screenshot or instrumented) or a documented manual check in the milestone's gate demonstrates it. Limits and rules referenced as §9.x are stated only there.

FR-1 Server bootstrap

The server starts with an empty database. The household is created from the command line on the Pi.

• AC-1.1 kvitt-server bootstrap on a database with no users creates an invite of kind admin_setup, prints its code (format §8.3), its landing link https://<KVITT_PUBLIC_HOST>/i/<CODE> (the base URL from KVITT_PUBLIC_URL), its expiry, and exits 0.
• AC-1.2 kvitt-server bootstrap on a database that has users prints already initialized to stderr and exits 2. It creates nothing.
• AC-1.3 Running kvitt-server bootstrap again before the first code is used cancels the previous admin_setup invite and prints a new one.
• AC-1.4 Accepting the admin_setup invite (FR-2) creates the admin user with the given display name and the first device, and returns a device token.
• AC-1.5 GET /setup/status returns {"initialized": false} before AC-1.4 and {"initialized": true} after.
• AC-1.6 kvitt-server pair-device --user <user_id> creates a device invite for an existing user and prints it like AC-1.1. This is the recovery path when the owner has lost every paired phone.

FR-2 Invites and pairing

• AC-2.1 The admin creates a partner invite from Settings. It is refused with household_full when two users exist. Creating a new partner invite cancels any pending one.
• AC-2.2 The admin creates a device invite for either user from Settings (to pair a second phone).
• AC-2.3 An invite is single-use and expires 72 hours after creation. An expired, cancelled, used or unknown code is refused with invite_invalid; the response does not reveal which.
• AC-2.4 Accepting an invite takes the code, a device name and (for admin_setup and partner) a display name. It returns a bearer token, the kind of the accepted invite (invite_kind, D-086), the user, the device and the household's users. For a partner invite it creates the member user. On a first pairing the app asks for the display name on S-1 (§13.3); a partner confirms it on S-2 (AC-2.10) (D-050).
• AC-2.5 GET /i/<CODE> serves an HTML landing page in Swedish if the request's Accept-Language prefers sv, English otherwise. It shows: the app name, "Download Kvitt" linking to the latest APK (FR-16), an "Open in Kvitt" button linking to kvitt://invite?server=<urlencoded KVITT_PUBLIC_URL>&code=<CODE> (followed by &from=<urlencoded name> when the request carries a valid from query parameter, D-087), the code in groups of 4, and one sentence of instructions (copy in §13.3, "Invite landing page"). It does not reveal whether the code is valid and contains no personal data of its own: the from name is only passed on into the kvitt://invite link and never shown on the page; an invalid from (not UTF-8 after percent-decoding, a control character, or more than 40 code points after trimming) is dropped and the page still opens (D-087). While no APK is published (E-5 would answer not_found) the page omits the download button. The page is sent with Referrer-Policy: no-referrer and Cache-Control: no-store. The 404 page (E-4 with a code outside 1 to 32 characters) shows only "Kvitt" and "404". Since the app gate (§8.5, D-126) the page opens in a browser only on the home LAN; from outside, a browser gets a closed connection, while the app opens the link (AC-2.6, autoVerify="false", so no App Links check depends on the page).
• AC-2.6 The app opens from kvitt://invite?server=…&code=…[&from=…] and from https://<kvitt.publicHost>/i/<CODE>[?from=…] (the manifest placeholder publicHost, D-121; unverified link, the user may get a chooser; the intent filter names no port, so it matches every port of the host and an older :8443 link still opens S-1 with the server it names; invite-link parsing drops an explicit default port, :443 for https and :80 for http, D-124) directly into the pairing screen with both fields filled. When the link names the inviting admin (from, E-12, D-087), S-1's help line names them (onboarding_code_help); links without a name (older links) still open, with the generic help line. The https link is declared with android:autoVerify="false". An invite link opened while the phone is paired is ignored: the app stays where it is and never re-pairs over live data (D-084). A link may name any server: as built, S-1 opens its server row expanded when the link's server is not the release default (RELEASE_SERVER_URL = https://<kvitt.publicHost>, D-121, D-124), so the address is visible and editable before pairing; v1 adds no confirmation step for an unusual server (security review L-6, D-116; a confirm step would need a design state, OQ-6).
• AC-2.7 The pairing screen also accepts manual entry: a server URL (prefilled with RELEASE_SERVER_URL in release builds, D-121) and the code. Codes are normalised per §8.3 before sending.
• AC-2.8 Release builds accept only https:// server URLs. Debug builds also accept http:// for localhost, 10.0.2.2 and private LAN addresses (10.*, 172.16.*-172.31.*, 192.168.*). The limit is enforced in code by SessionRepositoryImpl.normaliseServerUrl, not by the network security config, which cannot express IP ranges (§8.5, D-082). A release build therefore pairs with any https:// server a link or the user names; what S-1 shows then is in AC-2.6 (D-116).
• AC-2.9 After pairing, the app runs a full sync (§14.4) and then asks for the notification permission (Android POST_NOTIFICATIONS). As built (M8), the request is made after the first successful sync after pairing.
• AC-2.10 A partner pairing (E-3 invite_kind = partner, D-086) continues to a profile step (display name prefilled from the accept call, optional picture) before the Home screen. Every other pairing goes to Home, including a member pairing a second phone with a device invite.
• AC-2.11 The admin sees pending invites (kind, created, expiry) in Settings and can cancel each.
• AC-2.12 More than 10 failed invite accepts from one client IP within 60 minutes yield rate_limited for the rest of that window. A failed accept is any 4xx answer of E-3 other than 429. After the tenth failure, further accepts from that IP are refused with rate_limited until 60 minutes after the first counted failure; the window is fixed from the first counted request, not sliding (D-031).

FR-3 Devices and revocation

• AC-3.1 Settings lists devices: the admin sees all devices of both users; a member sees their own. Each row shows device name, owner, paired date, last seen date, app version (the version name, "Kvitt 1.1", once the device has reported one, else the version code; D-090), and "This device" for the current one.
• AC-3.2 The admin can revoke any device except the one in use (cannot_revoke_current_device). A member can revoke their own devices except the one in use. A member who names a device of the other user gets not_found, the same answer as for an unknown id, so the answer does not tell whose the device is (D-156, security review L-10; implemented in 07c36d2).
• AC-3.3 A revoked device's next request gets HTTP 401 device_revoked. The app then deletes its token, its local database and its cached pictures, and shows the "Device removed" screen with a "Pair again" button.
• AC-3.4 A revoked device never receives pushes again.
• AC-3.5 Devices are never deleted from the database; revocation sets revoked_at and clears the device's fcm_token (D-034).

FR-4 Profiles

• AC-4.1 Each user has a display name (limits §9.6) and an optional profile picture.
• AC-4.2 A user edits their own display name in Settings (online only). The change reaches the other phone through sync.
• AC-4.3 A user sets their own picture from the Android photo picker (no camera capture in v1) or removes it. Upload is online only.
• AC-4.4 The server accepts JPEG, PNG and WebP up to 5 MiB and at most 8000 × 8000 pixels, and also at most 16 000 000 pixels (width × height, for example 4000 × 4000) decoding to at most 64 MB (16 MP × 4 bytes, so a 16-bit image is refused above 8 MP), checked from the image header before decoding with the decoder's limits set as well, else image_invalid (D-114); it applies EXIF orientation, centre-crops to a square, re-encodes as JPEG quality 85 at 512 × 512 and 128 × 128, strips all metadata, and increments the user's picture_version (the first upload is version 1; after a removal the next version follows the highest one ever used, §10.4, D-030). PNG and WebP transparency is flattened onto white (D-034). Other input is refused with image_invalid, unsupported_media_type or payload_too_large.
• AC-4.5 Where no picture exists, the app shows the user's initials (first letter of the first two words of the display name, uppercase) on one of two colour tokens, avatar-1 and avatar-2 (values in U2's docs/ux/design-spec.md). A user's slot is a stable function of the user id, so the same user has the same colour on both phones (D-052).
• AC-4.6 The app caches pictures on disk (Coil) keyed by user id and picture_version, so they show offline.

FR-5 Household gate

• AC-5.1 Until the partner has joined, the admin's Home screen shows "Waiting for your partner" with the "Invite partner" action, and creating accounts, expenses, settlements and recurring templates is not offered. In that state SettlementRepository.start and recompute return null and save returns SaveResult.Invalid with a payer validation_failed error; nothing throws (§14.2.4, D-111).
• AC-5.2 The server refuses account creation, recurring template creation and any expense or settlement mutation with household_incomplete while fewer than two users exist. (The rule exists because every split refers to both users.)

FR-6 Expense accounts

• AC-6.1 Either user creates an account (online) with a name and a default split ratio. The editor starts at 50/50. Ratios are entered as percent with up to two decimals per user, the second user's value always being 100 minus the first; stored as bp (§9.1).
• AC-6.2 Account names are unique among non-deleted accounts, compared case-insensitively after trimming (Unicode lowercase). A duplicate is refused with name_taken.
• AC-6.3 Either user renames an account or changes its default ratio (online). A ratio change affects only expenses created afterwards; existing expenses keep the shares they were saved with.
• AC-6.4 Either user archives or unarchives an account (online), even with a non-zero balance. Archived accounts are hidden from the account pickers for new expenses and recurring templates, shown in a collapsed "Archived" section on Home, still count toward the global balance, still appear in analytics and can still be settled. Hiding is a picker rule only: the server accepts archived accounts and categories in E-28 and E-29 (as it does in sync pushes, §9.10).
• AC-6.5 Either user deletes an account (online) only when no non-deleted expense, no allocation of a non-deleted settlement and no non-deleted recurring template references it. Otherwise account_not_empty. Deletion is a soft delete (tombstone) so phones learn of it through sync.
• AC-6.6 Accounts are listed by created_at ascending, the order used by the settlement proposal (§9.4).
• AC-6.7 The account create and edit actions are disabled with a "Needs connection" hint when the phone is offline (§9.9).

FR-7 Categories

• AC-7.1 One global, editable category list. A category has a name, an icon token (§9.7) and a colour token (§9.7).
• AC-7.2 The database is seeded with exactly these fourteen default categories (fixed ids, §14.1; the four with sort_order 25, 45, 85 and 95 were added by migration 0002, §14.1.1, D-054), each shown with its localised default name until a user renames it:

default_key	English name	Swedish name	icon	color	sort_order
groceries	Groceries	Mat & hushåll	shopping_cart	green	10
restaurants	Dining (D-067)	Restaurang & café	restaurant	orange	20
housing	Housing	Boende	key	indigo	25
home	Home	Hem	home	brown	30
utilities	Utilities	Räkningar	bolt	yellow	40
insurance	Insurance	Försäkringar	shield	slate	45
transport	Transport	Transport	directions_car	blue	50
travel	Travel	Resor	flight	teal	60
entertainment	Entertainment	Nöje	movie	purple	70
health	Health	Hälsa	medical_services	red	80
children	Children	Barn	child_care	lime	85
shopping	Shopping	Shopping	shopping_bag	pink	90
fees	Fees & taxes	Avgifter & skatter	account_balance	amber	95
other	Other	Övrigt	category	grey	100

home keeps furniture, supplies, maintenance, electronics and services; rent and mortgage belong to housing (D-054).

• AC-7.3 Either user creates a category (online) with a name, icon and colour. New categories get sort_order = the maximum sort_order over non-deleted categories + 10 (D-034).
• AC-7.4 Either user renames, re-icons, recolours or reorders a category (online). Renaming a default category stores the custom name; "Reset name" (only for default categories) clears it so the localised name shows again.
• AC-7.5 Either user archives or unarchives a category. Archived categories are not offered for new expenses or templates but stay on existing ones and in analytics.
• AC-7.6 A category is deletable only if no non-deleted expense or non-deleted recurring template uses it (category_in_use otherwise). Default categories (with a default_key) cannot be deleted (category_is_default); they can be archived. Deletion is a soft delete.
• AC-7.7 Category names have no uniqueness rule.

FR-8 Expenses

• AC-8.1 An expense has: account, amount (öre), description, category, date, payer, split, notes, created-by, last-modified-by, timestamps. Limits in §9.6.
• AC-8.2 Either user creates, edits or deletes any expense, online or offline. The id is a client-generated UUIDv7.
• AC-8.3 The payer is either user. The editor defaults the payer to the current user.
• AC-8.4 The date is any date within §9.6 limits, past or future. It defaults to today in the phone's time zone. This date is the only date used in analytics and lists.
• AC-8.5 Split modes (enum §9.1): default (the account's default ratio, copied into the expense when saved), ratio (a custom ratio), exact (exact öre per user), full (the whole amount borne by one chosen user, who may be the payer or not). Share computation per §9.1.
• AC-8.6 The editor defaults: account = the account last used on this phone if still active, else the oldest active account; category = the category suggestion of §9.11 for a new expense, whose last step is the category last used in that account on this phone if still active, else other (D-049); when other is archived too and no active last-used category exists, the editor shows no category until the user picks one (v0.9); editing an existing expense keeps its category; split mode default. On the web "this phone" means this browser (localStorage, D-147).
• AC-8.7 Exact mode: the user types one user's share; the other user's share is the amount minus it and is shown read-only. A typed share larger than the amount blocks saving with an inline error.
• AC-8.8 Changing the account of an expense in mode default re-copies the new account's ratio. In other modes the split is kept.
• AC-8.9 Deleting asks for confirmation and is a soft delete. Deleted expenses disappear from lists, balances and analytics on both phones after sync.
• AC-8.10 Expense lists show, per row: category icon and colour, description, date, amount, and a one-line effect from the viewer's side ("You lent 205,00 kr", "You borrowed 205,00 kr", "Not involved" for full on the payer, matching §13 copy; Swedish "Du lånade ut 205,00 kr", "Du lånade 205,00 kr", "Inte inblandad", D-052). Rows are ordered by date descending, then created_at descending.
• AC-8.11 An expense created from a recurring template is an ordinary expense in every way (editable, deletable) and shows "Recurring" with the template name in the detail view.

FR-9 Recurring expenses

• AC-9.1 Either user creates, edits, pauses, resumes or deletes a recurring template (online). A template holds the expense fields (account, amount, description, category, payer, split mode and shares, notes) plus day_of_month (1-31), start_period and an optional end_period.
• AC-9.2 The server creates one expense per template per period at 06:00 Europe/Stockholm on the template's day. Days 29, 30 and 31 clamp to the last day of shorter months (day 31 in April creates on 30 April; day 29 in February 2027 creates on 28 February).
• AC-9.3 Generation rules (catch-up after downtime, idempotency, split resolution) are in §9.5.
• AC-9.4 Editing a template changes only expenses generated afterwards.
• AC-9.5 A generated expense that a user deletes is not recreated.
• AC-9.6 Each generated expense writes an audit entry with source = recurring and sends recurring_expense_created to every device of both users.
• AC-9.7 The template list shows each template's description, amount, account, day of month, paused state and next occurrence date (computed by the server, next_occurrence_date).
• AC-9.8 The editor's default start_period is the current month if day_of_month is today or later in the phone's time zone, else the next month. A new template's day_of_month defaults to today's day of the month, so the default start_period is the current month until the user picks an earlier day (D-072). The user may choose a start_period up to 12 months in the past (backfill) and any month in the future.

FR-10 Balances

• AC-10.1 Home shows one global balance between the two users from the viewer's side: " owes you X", "You owe X" or "All settled up".
• AC-10.2 Home lists every active account with its balance in the same wording, and archived accounts in a collapsed section.
• AC-10.3 The account screen shows that account's balance and its expenses and settlements interleaved by date.
• AC-10.4 Balances are computed on the phone from the local database with the domain function of §14.5, include pending (unsynced) local changes, exclude deleted rows, and update immediately after a local write.
• AC-10.5 The global balance equals the sum of the per-account balances, archived accounts included.

FR-11 Settlements

• AC-11.1 A settlement is a payment from one user to the other with an amount, a date, an optional note and one or more per-account allocations. Limits in §9.6.
• AC-11.2 The allocations' sum must equal the settlement amount. Each allocation is positive. An account appears at most once.
• AC-11.3 Global settle-up (from Home): the direction defaults to "the user who owes pays", the amount defaults to the absolute global balance (or empty when it is zero). The app computes the proposal with propose_allocation (§9.4, §14.5) and shows one editable row per proposed account plus "Add account" to add any other account (active or archived). The confirm button is enabled only when the allocations sum to the amount; the remaining difference is shown live.
• AC-11.4 Per-account settle-up (from the account screen) creates a settlement with exactly one allocation for that account; the amount defaults to the absolute account balance and the direction to "the user who owes in this account pays".
• AC-11.5 An allocation larger than the payer's current debt in that account is allowed (over-settling flips the account's sign) and is marked with a warning per row ("This settles more than is owed in "). The confirm dialog repeats the warning.
• AC-11.6 Settlements can be created, edited and deleted (soft delete) offline, by either user, like expenses. When editing, the proposal and warnings are computed with the edited settlement excluded from the balances. An edited settlement opens with its saved allocation rows counted as edited by the user, so changing the amount keeps them; "Suggest again" (settle_propose_again, "Föreslå igen") re-proposes (D-074).
• AC-11.7 A settlement row in lists shows " paid X" and the account count when more than one allocation exists. In an account's list (S-5) X is the settlement's allocation to that account, not the settlement total; everywhere else X is the total.
• AC-11.8 The server's POST /settlements/proposal returns exactly what the phone's propose_allocation returns for the same server state (verified by shared vectors). The phone always computes locally; the endpoint exists for parity tests and server-side tooling.

FR-12 Audit log and timeline

• AC-12.1 The server appends an audit entry for every accepted create, update and delete of an expense or settlement, from the app, the scheduler or the importer. Entries are never updated or deleted.
• AC-12.2 An entry records entity type, entity id, action, source, actor user, actor device (null for scheduler and importer), client time of the change, server time, and a field diff (§14.4.7).
• AC-12.3 Audit entries reach both phones through sync pull.
• AC-12.4 The expense and settlement detail views show a timeline, newest last, one line per entry, such as "Anna created this · 3 Oct 14:02", "You changed the amount from 400,00 kr to 412,00 kr · 3 Oct 18:30", "Anna deleted this". Diffs show field names in the UI language; ids are resolved to names (accounts, categories, users).
• AC-12.5 A pending local change not yet synced shows as a last timeline line "Your change is waiting to sync".

FR-13 Push notifications

• AC-13.1 When the server accepts a create, update or delete of an expense or settlement from a device of user U, it sends a push to every non-revoked device of the other user that has an FCM token. Types and payload in §14.6.
• AC-13.2 Recurring generation sends to every non-revoked device of both users.
• AC-13.3 The importer sends no pushes.
• AC-13.4 One POST /sync that produces more than 3 notifiable changes sends one sync_batch push instead of one per change.
• AC-13.5 The app shows the notification only after it has synced the change, built from local data in the phone's language (title and body copy in §13). If that sync fails within 20 seconds, it shows a generic text without amounts or descriptions.
• AC-13.6 Tapping a notification opens the detail view of the changed expense or settlement (S-8 or S-10). It opens Home for deletions, for sync_batch and for the generic notification (shown when the sync failed or the entity or its actor is missing locally) (D-085).
• AC-13.7 The app registers for push by Firebase Installation ID (D-083): it calls register() whenever it is paired and at each app start while paired, and every id Firebase hands to onRegistered(fid) is sent as fcm_token with PUT /devices/current/push-token (E-17). The server sends pushes to that id in the FCM HTTP v1 message.fid field (§14.6, D-096). When the device is revoked (AC-3.3) the app calls unregister(). A failed E-17 send (network error, 429, 5xx) is kept and sent again after each successful sync until the server accepts it; a newer id from onRegistered replaces the kept one (PushTokenRetry in :app, D-112).
• AC-13.8 No personal content (names, amounts, descriptions, notes) is placed in the FCM payload.
• AC-13.9 Notifications are posted with VISIBILITY_PRIVATE and a public version carrying the generic text "Kvitt" / "Open Kvitt to see it" (notif_generic_title, notif_generic_body), so a secure lock screen shows no description, amount, account or name (security review L-7, D-116).

FR-14 Analytics

• AC-14.1 Analytics (S-11, S-12) are computed on the phone from Room with the pure function of §14.5.4. They work offline and include pending local changes. Revised by D-133: the advanced analytics (per-category averages and trends per month, the two-month forecast per account) come from the server's /analytics/* endpoints (E-34 trends, E-35 forecast, rules §14.5.7, D-138), online only (§9.9), shown on the web (W-11) and in the app's Insights section on S-11 (W6, as built D-141 to D-143) (§15.8); the web client computes S-11 and S-12's equivalents in the browser with the same functions (§15.5).
• AC-14.2 Range presets: this_month, last_3_months, last_6_months, last_12_months, this_year, all_time, custom (start and end date pickers). "Last N months" means the current month and the N-1 months before it, whole months. Default last_6_months.
• AC-14.3 Granularity: month or week (ISO, Monday start). Default month.
• AC-14.4 Measure: household (sum of full expense amounts, whoever paid) or my_share (sum of the viewer's shares). Default household.
• AC-14.5 Group by: category or account. Default category.
• AC-14.6 Charts: (1) spend over time, a stacked bar per bucket coloured by group; (2) category breakdown for the range, horizontal bars sorted by amount descending with amount and percent; (3) account breakdown for the range, same form. A total for the range is shown above the charts. Settlements are never counted as spend.
• AC-14.7 Every bucket in the range appears, empty ones as zero. Buckets at the edges of a custom range count only dates inside the range.
• AC-14.8 Tapping a bar or a breakdown row opens a list of the expenses behind that number.
• AC-14.9 Deleted expenses are excluded; archived accounts and categories are included.
• AC-14.10 Percentages are rounded half-up to one decimal and may not sum to exactly 100.
• AC-14.11 A drill-down for one category or account over the range shows its spend per bucket as a line chart (every bucket, empty ones as zero), the range average as a dashed reference line, a trailing moving average over 3 buckets, and a caption comparing the latest whole bucket with the average in whole percent; its range and granularity can be changed on the drill-down without changing S-11 (D-128).

FR-15 Offline and sync

• AC-15.1 The phone holds a full local copy of: users, accounts, categories, recurring templates, expenses, settlements and audit entries (Room, §14.2).
• AC-15.2 Expenses and settlements can be created, edited and deleted offline. Accounts, categories, recurring templates, profile, pictures, invites and devices need the server; their actions are disabled offline with "Needs connection".
• AC-15.3 Sync runs on app start and every return to the foreground, 2 seconds after the last local write (debounced), every 15 minutes in the background through WorkManager (network constraint), and on every FCM data message (expedited one-off work, waited for up to 20 seconds, AC-13.5). A pull-to-refresh on Home (S-4) or account detail (S-5) also runs a sync, the same call as S-16 "Synka nu" (D-127). Only one sync runs at a time. WorkManager names in §14.4.1 (D-028).
• AC-15.4 The app shows a "Last synced" relative time and a pending-changes count on Home, and a sync status screen (§13).
• AC-15.5 Conflicts resolve by last-write-wins per row on the client updated_at, deletes are final, and rejected changes are shown to the user (§14.4).
• AC-15.6 A phone offline for 14 days with 200 local changes syncs all of them on reconnect (integration test with a scripted clock).

FR-16 In-app update

• AC-16.1 The server hosts the latest signed release APK and its metadata (§10.6).
• AC-16.2 Release builds call GET /apk/latest on every cold start and at most once per 6 hours while resumed (the manual check of AC-16.6 skips this throttle, D-140). When version_code is greater than the installed one, Home shows an "Update available" banner with the version name.
• AC-16.3 "Update" downloads the APK to the app's cache, verifies the size and SHA-256 from the metadata, and installs through PackageInstaller. The first time, Android asks the user to allow "Install unknown apps" for Kvitt; the app explains this beforehand: UpdateRepository emits UpdateState.NeedsInstallPermission once (the explanation-shown flag in prefs.preferences_pb, §14.2.2), and the next install() proceeds to the system prompt. On Samsung phones Auto Blocker must be off for the install: with it on, the system installer refuses the APK (observed on both phones, 2026-10-24: turning it off let the update install; D-156). The owner turns it off for an update and back on afterwards; the D-155 blocked text (update_install_blocked) names Auto Blocker (AC-16.7).
• AC-16.4 A verification failure deletes the file and shows "Download failed, try again".
• AC-16.5 Debug builds never check for updates.
• AC-16.6 "Check for update" on S-22 calls UpdateRepository.checkNow() (D-140; check() before v0.30), which returns an UpdateCheck (D-092, revising D-073): UpToDate (nothing newer published; a 404 from E-5 counts as up to date) reports "You have the latest version" (settings_about_up_to_date, "Du har den senaste versionen"); Failed (no answer or another error) reports "Could not reach the server" (common_could_not_reach_server); Available shows the update banner. Debug builds report UpToDate without a request (AC-16.5). S-22 "Check for update" always calls GET /apk/latest, whatever the 6-hour throttle of AC-16.2 says, and restarts that window; the automatic checks on cold start and resume keep the throttle (D-140).
• AC-16.7 If the system installer refuses or fails the install, Home and S-22 show the Error banner "Kunde inte installera uppdateringen" (update_install_failed) with the reason (blocked by the phone's security settings, update_install_blocked, or the installer's own message) and "Försök igen", which downloads again; declining the system dialog shows "Uppdatera" again without an error (D-155). The cached APK is deleted once the installer answers.

FR-17 Splitwise import

• AC-17.1 A one-off CLI kvitt-import (crate kvitt-import) imports Splitwise CSV exports, one file per Splitwise group, each into a Kvitt account named on the command line. Details §10.8.
• AC-17.2 Re-running the same import creates nothing new (stable import key, §10.8).
• AC-17.3 Splitwise categories map to Kvitt categories by the fixed table in §10.8; unknown names map to other and are listed in the summary.
• AC-17.4 Splitwise payments become settlements with one allocation.
• AC-17.5 --dry-run prints the summary (rows read, expenses, settlements, skipped duplicates, unknown categories, non-SEK rows, the reconciliation of §10.8) and writes nothing; it runs the whole import transaction and rolls it back, with the same exit status a real run would have (D-046).
• AC-17.6 Imported rows produce audit entries with source = import and no pushes.

FR-18 Backups and restore

• AC-18.1 Every night at 03:30 Europe/Stockholm the backup sidecar writes a consistent SQLite snapshot and a pictures archive, gzips them and uploads them to the owner's Google Drive folder with rclone. Nothing on Drive is ever deleted or overwritten. Verified by the owner on 2026-10-24: the first backup on the Kvitt Pi ran and its snapshot pair is in the Drive folder (D-156, §11.4).
• AC-18.2 A restore drill following §10.9 restores a backup on the Pi and both phones then sync correctly, documented in docs/validation/restore-drill.md.

FR-19 Localisation and formatting

• AC-19.1 Every user-visible string is a resource in values/strings.xml (English, the fallback) and values-sv/strings.xml (Swedish). No string literal appears in feature code. A lint or test in the Android gate fails on a key missing from either file. The APK carries only these two languages: android/app/build.gradle.kts sets androidResources.localeFilters to en, sv (G-8; 2bd6b58), so libraries' translations into other languages are not packaged.
• AC-19.2 Money formatting per §9.8, dates per §9.8.
• AC-19.3 Category default names and every enum shown to users have strings in both languages.

FR-20 Health

• AC-20.1 GET /health returns status, server version, schema version and a database check, unauthenticated, in under 100 ms on the Pi.
• AC-20.2 The docker healthcheck of the server service uses it.

FR-21 Web client

The web client of §15 (D-129 to D-134). Its acceptance criteria:

• AC-21.1 https://<KVITT_PUBLIC_HOST>/app/ serves the web client from the server image; every path under /app/ that is not a file serves index.html, except a missing assets/* file, which is 404 not_found (D-135); without the web files (KVITT_WEB_DIR missing) /app/* is 404 not_found (§15.4).
• AC-21.2 A browser logs in with an invite code through E-3 like a phone pairs (any of the three kinds), as device Web · <browser>; the token is kept in localStorage and sent as a bearer token; the browser appears on Devices and can be revoked from another device (§15.2).
• AC-21.3 A 401 forgets the token and shows the login page; device_revoked adds the S-18 message. Log out forgets the token and says that the browser stays on Devices until revoked.
• AC-21.4 Every page of §15.6 shows the server's current data: the household snapshot is pulled from GET /sync on load, on window focus and after every write; nothing but the token, the language choice and per-viewer conveniences survives a reload (§15.5).
• AC-21.5 Writes go to the server at once (POST /sync for expenses and settlements, REST for the rest); a failed write changes nothing and keeps the form's values; nothing is queued.
• AC-21.6 The web's money functions pass the vector files of §14.5.2's functions; its analytics functions pass resolve_range.json and spend_series.json; its category suggestion passes suggest_category.json (§15.3).
• AC-21.7 Swedish when the browser prefers Swedish, English otherwise; a choice on W-13 overrides it in that browser; every string exists in both languages.
• AC-21.8 From 720 px wide the layout has a sidebar; under 720 px one column with a bottom bar, usable at 360 px; light and dark follow prefers-color-scheme.
• AC-21.9 N opens a new expense, / the search, ? the shortcut help, Esc closes the open dialog or editor; N, / and ? do nothing while typing in a field.
• AC-21.10 Search finds non-deleted expenses by text in the description or notes, filtered by amount range, date range, account, category and payer; the filtered list exports as a CSV file (§15.7).
• AC-21.11 Accessibility as §13.1, for the web: every action reachable by keyboard with a visible focus, a label for every icon-only control, text contrast at least 4.5:1, nothing conveyed by colour alone, semantic headings and landmarks.
• AC-21.12 No service worker and no web app manifest; nothing is loaded from another origin at run time (§15.2).

FR-22 Card purchases

Each user may connect their own payment card; the server reads its purchases through Enable Banking and the card holder turns them into expenses (D-158 to D-176). Rules in §9.12 (CP-1 to CP-14); screens S-23 to S-27 (§13.3) and W-21 to W-23 (§15.6); endpoints E-36 to E-44 (§14.3.4). Its acceptance criteria:

• AC-22.1 Settings (S-13) has the row "Anslut kort" ("Connect card"), which opens S-24: the server's card catalogue (E-36), each card with its artwork. v0.35 has exactly one entry, sj_prio_mastercard (SJ Prio Mastercard, SEB Kort). A provider the server has no Enable Banking application for (CP-13) is listed as "Inte konfigurerat på servern" and cannot be tapped.
• AC-22.2 Tapping a card that is not connected opens S-25: the history choice (CP-3) and "Anslut med BankID". The app creates an authorisation attempt (E-37), opens the returned bank URL in a Custom Tab, and polls the attempt (E-38) while S-25 is open; the bank (BankID: app-to-app on the phone, QR on a computer) redirects to /cards/callback (E-39), whose page says the card is connected and links back to the app. Within 5 seconds of returning, S-25 shows "Kortet är anslutet" and opens S-23 (CP-2).
• AC-22.3 Only the card holder sees their connection and purchases. A device of the other user that names a connection or purchase id gets not_found (CP-11). Nothing about a card purchase is in GET /sync, the audit log, a push, S-11, S-12, E-34 or E-35 until it is turned into an expense, which is then an ordinary household expense in all of them.
• AC-22.4 The Kortköp tab (S-23, the second bottom destination, §13.2) lists the holder's purchases newest first, grouped by day, with the filters "Att hantera" (default), "Kopplade", "Ignorerade", "Alla"; pending purchases carry "Preliminär"; deposits and refunds (credit) appear only under "Alla" (CP-8). The list works offline from the phone's copy (§14.2.1).
• AC-22.5 The list updates by itself: the server fetches each active connection in the background at most 4 times per 24 hours (CP-4); "Uppdatera" and pull to refresh on S-23 ask the server for a fetch with the user present (CP-5); S-23 shows "Uppdaterad " of the last successful fetch.
• AC-22.6 "Skapa utgift" on a purchase opens S-7 prefilled (CP-9): amount, description from the merchant text, the purchase date, the card holder as payer, the account, the category of §9.11 and the account's default split; "Spara" saves the expense and links the purchase to it. From the Kortköp list that is: tap the purchase, tap "Skapa utgift", tap "Spara".
• AC-22.7 The purchase sheet lists the household's existing expenses that match the purchase (CP-10, same amount, within ±3 days, not linked yet, entered by either user); one tap links. A row in "Att hantera" with exactly one match shows the chip "Koppla till ", which links in one tap.
• AC-22.8 "Ignorera" moves a purchase to "Ignorerade" (private, undoable with "Ångra" and "Sluta ignorera"); "Ta bort koppling" moves a linked purchase back to "Att hantera"; deleting a linked expense, by either user, moves its purchase back to "Att hantera" (CP-9).
• AC-22.9 Account detail (S-5) offers "Från kortköp" while the viewer has a connection: S-27 lists the viewer's purchases to handle, and one tap opens S-7 prefilled with that account.
• AC-22.10 The expense detail (S-8) shows the card holder, and only the card holder, the line "Från kortköp: , " with "Ta bort koppling".
• AC-22.11 From 14 days before the consent ends (valid_until, CP-6) S-23 shows "Kortanslutningen upphör " with "Förnya med BankID"; after it ends, S-23 shows "Kortanslutningen har upphört", keeps the stored purchases, disables "Uppdatera" and offers "Förnya med BankID". Renewing keeps every purchase and its state.
• AC-22.12 "Koppla från" (S-26, with confirmation) revokes the session at Enable Banking, deletes the purchases neither linked nor ignored, and keeps the linked and ignored ones unless "Radera även kopplade och ignorerade köp" is ticked; expenses already created stay (CP-12).
• AC-22.13 Linking, unlinking, ignoring and "Skapa utgift" work offline on the phone; the link changes are kept on the phone and sent after the next successful sync push (CP-9). Connecting, renewing, "Uppdatera", the history setting and "Koppla från" need the server (§9.9).
• AC-22.14 No merchant text, amount, session id, authorisation code or state reaches a server log, an NPM log or a phone log (§8.7, D-163).
• AC-22.15 The web client (K3) has the same features: W-21 Kortköp, W-22 Anslut kort with BankID by QR in the browser, W-23 the connection's settings (§15.6).

---

5. Data model

This section explains the entities and their meaning. The exact server DDL is §14.1, the phone's Room entities §14.2, the wire JSON §14.3. Limits are in §9.6.

5.1 Entity overview

Entity	Id origin	Synced to phones	Written by phones	Notes
User	server	yes (pull)	REST only, own profile	Exactly two in a complete household
Device	server	no	REST only	One per paired app install
Invite	server	no	REST only, admin	Single-use pairing code
Account	server	yes (pull)	REST only	Expense account, like a Splitwise group
Account default share	with account	yes (inside account)	REST only	One row per user, sums to 10000 bp
Category	server (defaults seeded with fixed ids)	yes (pull)	REST only	Global list
Recurring template	server	yes (pull)	REST only	Monthly generator
Recurring template split	with template	yes (inside template)	REST only	Shares for modes ratio, exact, full
Expense	client (UUIDv7)	yes (pull and push)	sync push	Soft delete
Expense split	with expense	yes (inside expense)	sync push	One row per user
Settlement	client (UUIDv7)	yes (pull and push)	sync push	Soft delete
Settlement allocation	with settlement	yes (inside settlement)	sync push	One row per account
Audit entry	server	yes (pull)	never	Append-only
Sync mutation record	server	no	never	Idempotency of pushes
Sync sequence, meta	server	no (epoch is sent in pull)	never	Global server_version counter, sync_epoch
Card connection (D-167)	server	the holder's phones only, through GET /cards/sync (E-40), never GET /sync	REST only, its own user	One per user and card provider; holds the Enable Banking session (server only)
Card purchase (D-167)	server (from the bank's transactions)	the holder's phones only, through E-40	REST only (PUT /cards/purchases/{id}, E-44): link and ignore	Private to the card holder; card_version from card_sequence
Card auth attempt (D-162)	server	no	never (created by E-37)	Single-use state of one BankID connection attempt
Card sequence	server	no	never	card_version counter of card connections and purchases, separate from server_version

Local-only phone tables: sync_state and sync_rejections (§14.2), and card_sync_state (§14.2.2, D-173).

5.2 Ownership of fields

• server_version: an integer from one global, strictly increasing sequence. Every insert or update of a synced row (users, accounts, categories, recurring templates, expenses, settlements, audit entries) takes the next value. Child rows (shares, splits, allocations) have none; a change to a child bumps its parent. Phones never set it.
• created_at, updated_at of expenses and settlements are set by the phone's clock at the time of the local write and are the last-write-wins key. For server-written rows (all others, and expenses created by the scheduler or importer) they are the server clock.
• created_by_user_id is set by the server from the authenticated device's user when it first stores the row, never taken from the client. updated_by_user_id and updated_by_device_id are set by the server on every accepted write.
• deleted_at marks a tombstone. Tombstones are kept forever on both server and phone and are synced like any other row.
• archived_at (accounts, categories) hides an item from pickers; it never affects money.

5.3 Money

• Amounts are integer öre in signed 64-bit integers (Kotlin Long, Rust i64, SQLite INTEGER).
• An expense's shares, one per user, always sum exactly to its amount.
• Ratios are integer bp per user summing to 10000.
• A user's net position in an account is: what they paid for expenses, minus their shares, plus settlement allocations they paid, minus settlement allocations they received. The two users' net positions always sum to zero. A positive net means the other user owes them that much. Formal definition §9.3.

5.4 Relationships

• An expense belongs to one account and one category, has one payer and exactly two splits (one per user), and optionally references the recurring template and period it was generated for.
• A settlement has a payer (from_user_id), a recipient (to_user_id) and one or more allocations, each to one account.
• An audit entry references one expense or settlement by type and id.
• A device belongs to one user. An invite of kind device targets one user.
• References from synced rows point only at rows that are never hard-deleted, so a reference always resolves on the server. On the phone a reference may be briefly unresolved during a pull (§14.2); the UI shows such a row only after its references resolve.

5.5 What is not stored

• No balances, totals or analytics are stored anywhere; they are always computed from rows.
• No exchange rates, no currencies (SEK is implicit).
• No passwords. Tokens and invite codes are stored only as SHA-256 hashes.

---

6. Architecture & stack

6.1 System view

 Samsung S26 (owner)            Samsung S26+ (partner)
 ┌──────────────────┐           ┌──────────────────┐
 │ Kvitt app        │           │ Kvitt app        │
 │ Compose UI       │           │                  │
 │ domain (pure)    │           │                  │
 │ Room (full copy) │           │                  │
 └───────┬──────────┘           └────────┬─────────┘
         │ HTTPS :443 (bearer token)     │
         ▼                               ▼
   router: external 443 ──► Home Assistant Pi :443   (already in place for Home Assistant, D-124; external 80 too, for Let's Encrypt)
 ┌──────────────── Home Assistant Pi ────────────────┐
 │ Nginx Proxy Manager (TLS, Let's Encrypt, D-120)   │
 └─────────────────────────┬─────────────────────────┘
                           │ plain HTTP over the LAN, :8080
                           ▼
 ┌──────────────────── Kvitt Pi: Raspberry Pi 3, docker compose ─────────────────────┐
 │ server (axum, :8080 published on the LAN) ──► /data/kvitt.sqlite (WAL)            │
 │ backup (sqlite .backup + gzip nightly ──► rclone ──► Google Drive)                │
 └───────────────────────────────────────────────────────────────────────────────────┘
         │ FCM HTTP v1 (service account)          ▲ Pi pulls images
         ▼                                        │
   Firebase Cloud Messaging ──► phones      owner's M4 Mac: build linux/arm64 images ──► Gitea registry

For card purchases (D-160) the server, and only the server, calls the Enable Banking API (https://api.enablebanking.com) over outbound HTTPS from the Kvitt Pi; the phones and the browser never talk to Enable Banking. The user's browser (a Custom Tab on the phone) visits Enable Banking's and the bank's pages for the BankID step and is redirected back to https://<KVITT_PUBLIC_HOST>/cards/callback (E-39, §10.5.2).

A browser running the web client (§15) reaches the same server the same way: HTTPS to NPM, which lets /app/, the invite accept and bearer-token requests through from outside the LAN (§8.5, D-130), and plain HTTP to the server, which serves the web client's files from its own image (D-132).

6.2 Android app

Concern	Choice	Why
Language	Kotlin 2.x, latest stable	Owner's requirement
UI	Jetpack Compose, Material 3; Material 3 Expressive components where they are stable. The Material 3 artifact is pinned explicitly in the catalog (1.4.0 at M2b) alongside the Compose BOM. Against material3 1.4.0 only ShortNavigationBar of the Expressive set is public and used; every other Expressive API takes the fallback listed in D-064 (M6)	Native, modern, screenshot-testable
Min / target SDK	minSdk 36 (Android 16); compileSdk and targetSdk 37 (the latest stable API when M2b pinned them, in libs.versions.toml)	Both phones run Android 16; no legacy paths
Local DB	Room 3 (androidx.room3, 3.0.3 at M2b), KSP only, an SQLiteDriver with androidx.sqlite:sqlite-bundled, exported schema (D-012)	Full offline copy; migrations with tests
DI	Hilt. :data's DataModule provides implementations only; the bindings of the :core:model interfaces to them live in DataBindingsModule (@DisableInstallInCheck), which :app includes in both variants through di/AppDataModule.kt in src/main (D-041, revised by D-081)	Standard, works with WorkManager and ViewModels
HTTP	Ktor client (OkHttp engine), kotlinx.serialization JSON	Kotlin-first, multiplatform-style DTOs
Background	WorkManager (periodic 15 min sync, expedited sync)	Survives process death, respects Doze
Dates	kotlinx-datetime	Allowed in pure modules (no java.time)
Images	Coil (Compose) with an auth header interceptor	Disk cache for offline avatars
Charts	Compose Canvas in :core:design, no chart library (D-063). Vico 3.3.1 cannot give the per-bar TalkBack nodes and tap targets, 2 dp segment gaps, corner radii on the whole bar (10/4 at M6; top 4, bottom 2 dp since D-097) and an axis gutter growing at 200 % that docs/ux/design-spec.md §3.10 requires. Vico was removed from the version catalog on 2026-10-18 (a312758); it was never used	The three charts are small; the design spec's accessibility rules need per-bar control
Push	Firebase Cloud Messaging (firebase-messaging 26.0.0 through the Firebase BoM 35.0.2, google-services plugin 4.5.0; registration by Firebase Installation ID, D-083), only inside :adapter:fcm	Free tier; vendor isolated per CLAUDE.md
Secrets	Android Keystore: an AES-256-GCM key (non-exportable) encrypts the device token; ciphertext in a private DataStore file	EncryptedSharedPreferences is deprecated
Build	Gradle with version catalog android/gradle/libs.versions.toml, Gradle daemon on JDK 25 (pinned), bytecode target Java 17. With AGP 9, check runs only the debug unit-test variant. versionCode and versionName come from the Gradle properties kvitt.versionCode and kvitt.versionName, defaulting to 1 and dev (§10.6)	Existing pin
Tests	JUnit, Compose screenshot tests with Roborazzi (1.76.0 at M2b) on Robolectric (4.17) with @Config(sdk = [36]) (D-010), Room tests (DAOs and migrations) on Robolectric with the framework SQLite driver, migration tests built from the exported schema JSON rather than room3-testing (D-042), Ktor MockEngine, WorkManager's test WorkManager from androidx.work:work-testing (a testImplementation of :data, the same version as work-runtime, c366fbd). Unit tests run on JDK 25 with --add-exports java.base/jdk.internal.access and --add-opens java.base/java.io for Robolectric, set in build-logic for every Android module (D-013). failOnNoDiscoveredTests is off only for modules without src/test (the shells) and on everywhere else (D-014)	No mocking libraries (CLAUDE.md)
Typeface	The Material 3 default typeface; the app bundles no font file (D-020)	No licence step, no font resource
App icon	Adaptive launcher icon, vectors only (D-095): android/app/src/main/res/mipmap-anydpi/ic_launcher.xml with background colour #9C5238 (the light theme's primary, values/ic_launcher_colors.xml) and foreground and monochrome layers (drawable/ic_launcher_foreground.xml, drawable/ic_launcher_monochrome.xml) drawing the receipt_long app mark at 48 dp, centred in the 108 dp canvas; the manifest's android:icon and android:roundIcon point at it, which clears lint MissingApplicationIcon	No raster assets; themed icons use the monochrome layer

Module graph (directory android/):

Module	Kind	Contents	May depend on
:core:model	pure Kotlin/JVM	Domain types (§14.5.1), analytics types (§14.5.4, package se.hagstedt.kvitt.model.analytics), *State classes, repository interfaces (§14.2.4)	kotlin, kotlinx
:domain	pure Kotlin/JVM	Split, balance, allocation, analytics functions (§14.5); test-vector tests	:core:model
:core:design	Android library	Built by M6 (7730a31) from docs/ux/design-spec.md §2 and §3: KvittTheme, tokens (KvittColors, KvittShapes, KvittMotion, which holds only the seesaw spring; navigation has no motion, D-108), typography, shared components (money text, avatar, category tile and pickers, balance header, sync pill, banners, charts drawn with Canvas, D-063; the ledger rows for expenses and settlements used by S-5, S-12 and S-16; the expense editor fields used by S-7 and S-19, D-019), MoneyFormatter, DateFormatter, the shared failure texts (format/Failures.kt: FAILURE_NETWORK, commonFailureText), the shared limits (format/Limits.kt: BP_TOTAL, DISPLAY_NAME_MAX, DESCRIPTION_MAX, NOTES_MAX, FIRST_DATE, DAYS_AHEAD_MAX, §9.6) and savedSplitLabel (S-8, S-16), shared strings (D-118). Its test fixtures (src/testFixtures, package se.hagstedt.kvitt.design.testing) are the shared test support of every Android module (D-118); they are not a module	:core:model
:core:fakes	Android library, used only by tests, screenshot tests and debug previews	Scenario-driven fakes of every repository interface (they call :domain for computed values so fakes never disagree with the real rules)	:core:model, :domain
:data	Android library	Room DB, DAOs, entities, Ktor API client and DTOs, sync engine, WorkManager workers, token store, repository implementations, APK updater	:core:model, :domain
:adapter:fcm	Android library	FirebaseMessagingService, registration by Firebase Installation ID (D-083), maps messages to PushEvent (:core:model, model/Push.kt, moved there by M12e, D-095) through PushMapping; PushListener stays in the adapter	:core:model
:feature:onboarding	Android library	Pairing, partner profile step, waiting for partner, device removed	:core:model, :core:design
:feature:home	Android library	Home (global balance, accounts), sync status, update banner	:core:model, :core:design
:feature:account	Android library	Account detail, account editor	:core:model, :core:design
:feature:expense	Android library	Expense editor, expense detail and timeline	:core:model, :core:design
:feature:settle	Android library	Settle up (global and per account), settlement detail and timeline	:core:model, :core:design
:feature:analytics	Android library	Analytics screen and drill-down list	:core:model, :core:design
:feature:settings	Android library	Settings hub, profile, categories, recurring templates, devices, invites, about	:core:model, :core:design
:feature:cards	Android library (D-173, K2)	Kortköp tab (S-23) with the purchase sheet, Anslut kort (S-24), connect (S-25), the connection's settings (S-26), "Från kortköp" (S-27), the card artwork (CardArt)	:core:model, :core:design
:app	Android application	MainActivity, navigation graph, Hilt wiring, deep links, notification channel and building, Application class	everything

Screenshot tests (D-010). roborazzi.test.verify=true in android/gradle.properties makes every unit-test run, and so check, compare renders with the committed goldens. An intended change is re-recorded with tools/gradle-serial.sh recordRoborazziDebug, and every changed PNG is opened before committing. AGP's Compose Preview Screenshot Testing plugin was still alpha when M2b chose. Golden layout (D-098, M8c, revises D-066): three goldens per component sheet or screen state, <name>_sv_light.png, <name>_sv_dark.png and <name>_en_light.png (English covers string length, dark covers the theme; there is no en_dark), plus <name>_sv_light_200.png at 200 % font scale for the long states; :app's empty_screen_<light|dark>.png are the only other names. The content is composed once and language, theme and font scale are switched through a configuration context, so Compose's non-linear font scaling still applies. Every capture renders at 1x density through the Robolectric qualifier w411dp-h<height>dp-mdpi, so a full screen of 411 × 891 dp is 411 × 891 px. Every committed PNG (goldens and the docs/ux/ mock-ups) is compressed losslessly with oxipng -o 4 --strip safe before committing (7c453d8); Roborazzi verifies against the compressed files. Feature modules follow the same layout: each feature module has Roborazzi screenshot tests of its screen states with goldens in src/test/screenshots/, rendered full screen. A screen harness renders one more frame and idles the main looper before each capture; without that :feature:home and :feature:account captured the previous variant, so their committed sv_dark (and some _sv_light_200 and dialog) goldens were one variant stale, fixed and re-recorded in dc7a296 and 5b2ed37. The reduction took the goldens from 1143 PNGs and 131 MB to 865 and 26 MB, the mock-ups from 36.8 to 26.0 MB, for a small repository on the home Gitea server. Since the Android overhaul (c582363, D-118) the harness is shared: :core:design's test fixtures (src/testFixtures, package se.hagstedt.kvitt.design.testing) hold Variant, TestClock, TestEnvironment, ScreenSnapshots with the capture modes Root, Screen and ScreenWhenIdle, MainDispatcherRule and withMain, consumed as testImplementation(testFixtures(project(":core:design"))). Test fixtures are not a module, so the module graph below is unchanged; the architecture check rejects a module's test fixtures in any configuration other than a test configuration. The convention plugin kvitt.android.screenshots wires Roborazzi (plugin, outputDir src/test/screenshots) and the test libraries; feature build scripts carry no screenshot block.

Hilt wiring (D-081, M8). Both variants bind every :core:model interface to :data: android/app/src/main/.../di/AppDataModule.kt includes DataBindingsModule (D-041), and AppBuildInfo (defined in :data's di/DataModule.kt, provided by :app's di/AppBuildInfoModule.kt, §14.2.4) comes from BuildConfig in both variants and also carries RELEASE_SERVER_URL as releaseServerUrl (D-122). The debug fakes module (a41f240) and the release-only data module were deleted by M8; no Hilt module lives in src/debug or src/release. Fakes live only in test source sets and feature previews and never reach an installed build; :app's unit tests run on a plain Application, not the Hilt application.

Features never call :domain directly: repositories return computed state (balances, previews, proposals), implemented in :data with :domain. The architecture check (Gradle task in check, owned by milestone M2b) fails the build on any other dependency edge and on java.time, java.io or android.* imports in :core:model and :domain.

Feature convention (D-017). Binding for every feature module (worked example and the stateless overload used by previews in android/README.md):

• Each feature exposes one composable entry point per screen. The entry point takes a ViewModel provided with hiltViewModel() and its navigation as plain lambdas (for example onOpenExpense: (ExpenseId) -> Unit, onBack: () -> Unit).
• Features never reference other features or the NavHost. :app owns the NavHost and connects the lambdas to routes.
• ViewModels receive repositories through the :core:model interfaces (§14.2.4). :app binds the interfaces through Hilt to :data; bindings to :core:fakes exist only in test and debug-preview source sets and never reach a release build.
• Shared UI that two features need is built in :core:design by M6 (D-019); a feature never copies another feature's component.
• Strings: :app holds only the app name; :core:design holds the shared strings (including the notification copy and channel name of §13.3 and §14.6, which :app uses); each feature module holds its own. Lint MissingTranslation is an error in every module. Keys of a feature module are prefixed by the feature name (home_, account_, expense_, ...); keys in :core:design never start with a feature name. This rule wins over any other key convention (§13.4, §14.7).

Fakes. Every fake in :core:fakes has at least the empty scenario (D-018): the household is complete (two named users, no pictures), there are no accounts, the categories are exactly the fourteen defaults of AC-7.2 (D-054), and there are no expenses, settlements, templates, rejections or pending changes. Feature agents add their own scenarios (§11.3).

6.3 Server

Concern	Choice	Why
Language	Rust stable, edition 2024; the exact release pinned in server/rust-toolchain.toml (1.99.1 at M2a) and the same tag in the Dockerfile (§10.3)	Owner's requirement; small RSS on a 1 GB Pi
HTTP	axum on tokio (multi-thread runtime, 2 worker threads)	Mature, small
DB	SQLite via sqlx, WAL mode, migrations embedded with sqlx::migrate!	One file, easy backup, ample for two users
Serialization	serde, serde_json	Standard
OpenAPI	utoipa generates the document from code; contracts/openapi.yaml is the committed contract; a test asserts the generated document equals it (§14.3)	One contract, checked by the gate
Logging	tracing, tracing-subscriber, JSON lines to stdout	Docker log rotation; no personal content (§8.7)
Time	chrono with chrono-tz for Europe/Stockholm (M2a confirmed; no other time crate)	DST-correct scheduling
Ids	uuid crate, v7	Same format as phones
Images	image crate (decode JPEG/PNG/WebP, encode JPEG)	Pure Rust, no system libs
HTTP client (FCM)	reqwest with rustls (crypto provider aws-lc-rs, certificates checked by the platform verifier); needs a C toolchain at build time and CA roots in the image (§10.3)	No OpenSSL on the image
FCM auth	Service-account JWT (RS256, jsonwebtoken crate, header kid = the key file's private_key_id) exchanged at https://oauth2.googleapis.com/token for an access token with scope https://www.googleapis.com/auth/firebase.messaging, cached until 5 minutes before expiry	HTTP v1 API needs OAuth2
Scheduler	A tokio task inside kvitt-server (no extra crate)	One process, simple
Card purchases (D-160, K1)	kvitt-server module src/cards/: the provider registry (providers.rs), the CardSource trait and its one adapter src/cards/enable_banking/ (the only code that names the vendor or reads its JSON; it maps it into Kvitt's own records), fetching and de-duplication (§9.12), the background poller (started from src/tasks/), the callback page; HTTP to Enable Banking through the existing reqwest client with rustls, JWTs signed RS256 with jsonwebtoken (both already in the stack)	Vendor isolated per CLAUDE.md; no new crate

Cargo workspace (directory server/):

Crate	Kind	Contents
kvitt-domain	library, no I/O	Money types, split, balance, allocation, settlement validation (§14.5), next_occurrence_date and the day clamping of §9.5 (D-015), test-vector tests. Depends only on serde; serde_json is a dev-dependency of the vector tests. Ids are plain strings (§14.5.1), so no uuid
kvitt-server	binary kvitt-server	Config, DB, migrations, HTTP API, auth, sync, audit, push, scheduler, pictures, APK, CLI subcommands (§10.4)
kvitt-import	binary kvitt-import	Splitwise CSV importer (§10.8). Depends on kvitt-domain and reuses kvitt-server as a library for DB access and audit writing (kvitt-server exposes a lib.rs)

Server seams (D-015). So that M3, M4 and M9 work in parallel on M2a's skeleton:

• Middleware in router.rs (M2a): the X-Kvitt-Protocol check (426 protocol_unsupported), the X-Kvitt-Server-Version response header and the §8.6 body limits (1 MiB, 5 MiB for PUT /me/picture) are layers in src/router.rs. On authenticated routes the protocol check runs before the token check, so a request with a bad protocol header and a bad token gets 426, not 401. M3's rate limit (§8.6, AC-2.12) is a layer defined in src/api/rate_limit.rs and attached at one line in router.rs that M2a marks with a comment; that line is the only one M3 edits in router.rs.
• Background tasks: M2a creates src/tasks/mod.rs with a start function that serve calls once after migrations (initially doing nothing). M4 owns src/tasks/** and starts the scheduler, the push sender and the sync_mutations pruning from it. As M4 built it (D-039): tasks::start returns the AppState with the real push queue installed, and serve builds the router from that returned state. Since the server overhaul (6c405e1) it is a synchronous fn start(AppState) -> AppState (it never awaited or failed); D-039 holds.
• Audit and push interfaces: M2a defines the traits AuditWriter (in src/audit/) and PushQueue (in src/push/) with no-op implementations, and passes them through the application state (AppState.audit, AppState.push). M4 replaces the implementations (audit writer and diff of §14.4.7, FCM queue of §14.6); M3 and M9 only call the traits. Since M4 (D-039): AppState::new holds SqlAuditWriter by default and NoopAuditWriter no longer exists; NoopPushQueue stays as the queue when push is disabled (§14.6), and tasks::start installs the bounded PushHub otherwise. As M2a built them (exact signatures in server/README.md):
  • AuditWriter::write takes the caller's open connection inside its BEGIN IMMEDIATE transaction and one AuditEvent (entity type and id, action, source, actor user and device, client_at, server_at, and the wire object before the change, absent for a create, and after it, as JSON), and returns the new audit entry's id or an AppError. The writer derives changes (§14.4.7) and takes the entry's server_version from that same transaction.
  • PushQueue::enqueue takes one PushMessage (push type, one of the eight of §14.6; entity id or none; actor user id; count). It never blocks and never fails; callers call it after commit.
• Recurring generation: M2a implements next_occurrence_date and the day clamping in kvitt-domain (§14.5.2). M3 writes the one function that generates the due periods of one template (§9.5: candidate periods, one transaction per candidate, audit through AuditWriter, push through PushQueue) in src/api/recurring.rs, used by E-28 and E-29; M4's scheduler calls that function for every template. M4 therefore lands after M3 (it may start in parallel and rebases on M3 before its gate).

6.4 Why these choices

• Phone computes balances and analytics. Offline is a hard requirement and the data set is small (six years of two-person history is a few thousand rows). Computing on the phone keeps the server dumb and the Pi idle.
• SQLite over Postgres. Postgres alone would use a large share of the Pi's 1 GB. SQLite in WAL mode handles two users trivially and backs up as one file.
• Global server_version sequence. One integer cursor per phone is the simplest correct incremental sync. SQLite's single writer, with every write in a BEGIN IMMEDIATE transaction, makes versions commit in order, so a reader never sees a gap that later fills.
• Last-write-wins on client time. Two people rarely edit the same expense concurrently; LWW with an audit trail lets them see and fix the rare collision. Clock-skew protection is in §14.4.
• Push carries ids only. Personal data does not pass through Google; the phone syncs and builds the text locally.
• No Play Store. Two users; a self-hosted APK with PackageInstaller is enough.
• Domain rules twice, one test suite. Kotlin and Rust implement the same pure functions and must pass the same JSON vectors, so phone and server agree to the öre.

---

7. API outline

Base URL: https://<KVITT_PUBLIC_HOST> (the value of KVITT_PUBLIC_URL, port 443, D-124; KVITT_PUBLIC_HOST is the Kvitt host name (KVITT_PUBLIC_HOST, owner-chosen, recorded in HANDOFF), D-120). All paths below are relative to it. There is no path prefix and no API version in the path; the protocol version travels in a header (§14.3.1).

#	Method	Path	Auth	Purpose
E-1	GET	/health	none	Liveness and DB check; S-22 shows its server_version and schema_version (D-110)
E-2	GET	/setup/status	none	Whether the household has been bootstrapped
E-3	POST	/invites/accept	none	Pair a device with an invite code (all three invite kinds)
E-4	GET	/i/{code}	none	Invite landing page (HTML)
E-5	GET	/apk/latest	none	Latest APK metadata
E-6	GET	/apk/files/{file_name}	none	APK download
E-7	GET	/me	device	Current user, device and household users
E-8	PATCH	/me	device	Change own display name
E-9	PUT	/me/picture	device	Upload own picture
E-10	DELETE	/me/picture	device	Remove own picture
E-11	GET	/users/{user_id}/picture	device	Download a user's picture
E-12	POST	/invites	admin	Create a partner or device invite
E-13	GET	/invites	admin	List pending invites
E-14	DELETE	/invites/{invite_id}	admin	Cancel an invite
E-15	GET	/devices	device	List devices (admin: all; member: own)
E-16	DELETE	/devices/{device_id}	device	Revoke a device
E-17	PUT	/devices/current/push-token	device	Set or clear this device's FCM token
E-18	POST	/accounts	device	Create account
E-19	PATCH	/accounts/{account_id}	device	Rename, change default ratio
E-20	POST	/accounts/{account_id}/archive	device	Archive
E-21	POST	/accounts/{account_id}/unarchive	device	Unarchive
E-22	DELETE	/accounts/{account_id}	device	Soft delete when empty
E-23	POST	/categories	device	Create category
E-24	PATCH	/categories/{category_id}	device	Rename, icon, colour, order, reset name
E-25	POST	/categories/{category_id}/archive	device	Archive
E-26	POST	/categories/{category_id}/unarchive	device	Unarchive
E-27	DELETE	/categories/{category_id}	device	Soft delete when unused and not default
E-28	POST	/recurring-templates	device	Create template
E-29	PATCH	/recurring-templates/{template_id}	device	Edit, pause, resume
E-30	DELETE	/recurring-templates/{template_id}	device	Soft delete
E-31	GET	/sync	device	Pull changes since a cursor
E-32	POST	/sync	device	Push local expense and settlement changes
E-33	POST	/settlements/proposal	device	Server-side allocation proposal
E-34	GET	/analytics/trends	device	Spending per month, averages and trends, household and per category (D-133, D-138)
E-35	GET	/analytics/forecast	device	Forecast of the next two calendar months per account (D-133, D-138)
E-36	GET	/cards/providers	device	The card catalogue: supported cards, artwork key, whether this server can connect them for the caller (D-160)
E-37	POST	/cards/auth	device	Start connecting (or renewing) a card: an authorisation attempt and the bank URL (D-162)
E-38	GET	/cards/auth/{attempt_id}	device	Status of the caller's authorisation attempt (D-162)
E-39	GET	/cards/callback	none	The bank's redirect target: finishes the attempt, HTML page (D-162, D-163)
E-40	GET	/cards/sync	device	The caller's card connections and purchases since a card cursor (D-167)
E-41	PATCH	/cards/connections/{connection_id}	device	Shorten the history setting (D-164)
E-42	POST	/cards/connections/{connection_id}/refresh	device	Fetch from the bank now, user present (D-165)
E-43	DELETE	/cards/connections/{connection_id}	device	Disconnect (D-167)
E-44	PUT	/cards/purchases/{purchase_id}	device	Link to an expense, unlink, ignore (D-169)

Reads of accounts, categories, templates, expenses, settlements and audit entries happen only through GET /sync; E-34 and E-35 are computed read-only views over them (§14.5.7), not a second way to read rows. Card connections and purchases are not household rows: they are read only through E-40, by their holder (D-161). The web client's static files under /app/ (§15.4, D-135) are not API endpoints: they have no E-number, no protocol check and no entry in contracts/openapi.yaml. Every REST write that changes a synced row returns that row in its wire form (§14.3.3), with its new server_version, so the phone can store it immediately.

Request and response shapes, error codes and status codes: §14.3. The OpenAPI 3.1 file contracts/openapi.yaml is written by milestone M1 from §14.3, which is binding.

---

8. Auth & security

8.1 Threat model

Two trusted users. The server is on the public internet on port 443, through NPM (D-120, D-124); outside the home LAN NPM passes only requests that carry the app key (§8.5, D-126). Threats in scope: random internet scanners, a stolen or lost phone, leaked invite links, a compromised backup location, accidental personal data in logs or push payloads. Out of scope: a malicious partner, an attacker with physical access to the Pi. Accepted risk (owner, 2026-10-19, security review M-1): the Drive backups stay unencrypted and the rclone token keeps the full drive scope, so a compromised Google account or rclone.conf exposes every backup (§8.7, §10.9).

Card purchases (D-161, D-163) add: the Enable Banking application's private key (in secrets/cards/ on the Pi, never in the database or a backup) and the Enable Banking session ids (in the database) are credentials to read the connected cards' transactions; a session id alone is useless without the private key, so a leaked backup or database does not expose the cards, and a leaked key without the database names no session. Kvitt can never pay or move money: the access is PSD2 account information only. In scope also: a forged or replayed bank redirect (single-use state bound to user and device, short expiry, CP-2), the authorisation code in a URL reaching a log (/cards/callback is never logged, §10.5.2), and one user seeing the other's card purchases (holder-only authorization, §8.4). Card purchases are personal content: everything §8.7 says about descriptions and amounts applies to merchant texts and card amounts.

8.2 Device tokens

• On a successful invite accept the server generates 32 random bytes from the OS CSPRNG and returns the token kvt_ + base64url without padding of those bytes (47 characters total).
• The server stores only token_hash = lowercase hex SHA-256 of the full token string.
• Tokens do not expire. They stop working only on revocation.
• Every authenticated request sends Authorization: Bearer <token>. The server hashes it, looks up a device with that hash and revoked_at IS NULL, and loads the user. Missing or unknown token: 401 unauthorized. Revoked: 401 device_revoked.
• The server updates devices.last_seen_at, devices.app_version_code and devices.app_version_name at most once per hour per device. That update sets app_version_code only when the request carries X-Kvitt-App-Version and its value parses as an integer, and app_version_name only when the request carries X-Kvitt-App-Version-Name with 1 to 32 characters after trimming (D-090); otherwise the stored value is kept. E-3 stores both from the accepting request.
• On the phone the token is encrypted with an Android Keystore AES-256-GCM key (alias kvitt_token_key, setUserAuthenticationRequired(false), no export) and the ciphertext and IV are stored in DataStore file auth.preferences_pb. The server base URL, user id and device id are stored next to it in plain text, together with the pairing status (D-043).
• The token is never logged, never put in a URL, never included in a crash report or screenshot.

8.3 Invite codes

• 12 characters from the Crockford base32 alphabet 0123456789ABCDEFGHJKMNPQRSTVWXYZ (60 bits), generated from the CSPRNG.
• Displayed as three groups of four separated by -, as 7K3M-QX9D-2HPA. URLs carry the 12 characters without hyphens.
• Normalisation before hashing or sending: uppercase; remove - and spaces; replace O with 0 and I and L with 1. A normalised code that is not exactly 12 alphabet characters is invite_invalid.
• Stored as code_hash = lowercase hex SHA-256 of the normalised code.
• Single-use, 72-hour expiry, cancellable. Rate limit in AC-2.12.

8.4 Authorization rules

Action	admin	member
All expense, settlement, account, category, recurring template operations	yes	yes
Edit own display name and picture	yes	yes
Edit the other user's display name or picture	no	no
Create, list, cancel invites	yes	no (forbidden)
List devices	all	own only
Revoke a device	any except current	own except current (another user's device: not_found, D-156)
Card connections and purchases (E-37 to E-44)	own only; the other user's: not_found (D-161)	own only; the other user's: not_found (D-161)

8.5 Transport

• TLS terminates in the owner's Nginx Proxy Manager (NPM) on the Home Assistant Pi, with NPM's Let's Encrypt certificate for the Kvitt host name (KVITT_PUBLIC_HOST, owner-chosen, recorded in HANDOFF), on the default HTTPS port 443 (D-124); the router forwards external TCP 443 to the Home Assistant Pi's 443 (NPM), already in place for Home Assistant; nothing is forwarded to the Kvitt Pi (§10.1, §10.5, D-120, D-124). TLS 1.2 minimum, NPM defaults otherwise. NPM forwards plain HTTP over the home LAN to the server's port 8080 on the Kvitt Pi (accepted by the owner, D-120).
• App gate (D-126, owner decision 2026-10-21): NPM closes the connection (return 444, nothing sent) of every request that neither carries the header X-Kvitt-App: <key> with the app key nor comes from the home LAN 192.168.1.0/24. Every route is covered, /health, /setup/status, /invites/accept, /i/{code} and /apk/* included; only Let's Encrypt's /.well-known/acme-challenge/, which NPM serves from its own folder, passes (§10.5.2). D-130 later lets the web client's requests through (below). The LAN check reads nginx's $realip_remote_addr, the address that really connected, because NPM's real_ip_header X-Real-IP for private peers lets a client set $remote_addr. The release app sends X-Kvitt-App on every request when its build carries the key: the Gradle property kvitt.appKey (-Pkvitt.appKey=…, else the key kvitt.appKey in android/local.properties, else empty), 16 to 128 printable ASCII characters without white space or the build stops with a message giving the length, never the value; exposed as BuildConfig.APP_KEY and to :data as AppBuildInfo.appKey (whose toString hides it); added in KvittApi's common headers (every API call: /health, /apk/latest, /apk/files/{file_name}, /invites/accept included) and in PictureAuth for profile pictures from the paired server; an empty key sends no header (debug builds against the development stack need none). The key is generated by the owner (openssl rand -hex 32) and lives only in android/local.properties and NPM's Custom Nginx Configuration: never in git, never in .env, never printed in docs or logs. The Rust server neither sees nor checks the header and contracts/openapi.yaml is unchanged (§14.3.1). The per-device bearer token stays the authentication (§8.2); the gate is a perimeter that keeps scanners and anyone without the app from the server. On the home LAN the "secret" is the Wi-Fi password, and the owner controls the APK's distribution (he installs it on both phones). Rotation: a second if line with the new key next to the old in NPM, the new APK through the update path (FR-16), then the old line removed. Accepted: the invite landing page works only on the LAN; /health from outside without the header gets a closed connection, so the outside check is the app's About screen (S-22) or curl -H "X-Kvitt-App: $KEY"; a leaked APK leaks the key until rotation; nothing at home protects against a bandwidth flood. Web client (D-130, extends D-126): from outside the LAN three more kinds of request pass without the key, because a browser cannot carry it: a path that is /app or starts with /app/ (the web client's files), POST /invites/accept (the web login; AC-2.12's lockout bounds guessing), and a request with an Authorization: Bearer header whose path does not start with /health, /setup/, /i/ or /apk/ (the server checks the token; an unknown one gets 401 and counts against its address's unauthenticated limit, §8.6, the H-1 fix, D-115). /health, /setup/status, /i/{code} and /apk/* stay LAN-or-key only. Consequence, accepted: the server's authenticated routes are reachable from the internet with a wrong token (401, at most 60 per minute per address), which the security review's threat model already assumed before D-126 (§15.2).
• Release builds' network security config (android/app/src/main/res/xml/network_security_config.xml): cleartext disabled, system trust anchors only, unless the pinned-root switch is on, in which case a pinned root replaces the system anchors for one domain only (available but unprepared since D-120, §10.5.3). The pinned-root config is generated at build time (task generatePinnedRootNetworkSecurityConfig) from the template android/app/src/releasePinnedRoot/network_security_config.xml with the domain kvitt.publicHost (D-121), into the release resources only when the Gradle property kvitt.tls.pinnedRoot is true (D-082); the build stops with a message while android/app/src/release/res/raw/kvitt_root_ca.crt is not committed (038c603).
• Debug builds override the config in android/app/src/debug and allow cleartext to every host, because a network security config cannot express IP ranges; the AC-2.8 limit (localhost, 10.0.2.2, private LAN addresses) is enforced by SessionRepositoryImpl.normaliseServerUrl. Lint's InsecureBaseConfiguration warning on the debug config is intended (D-082).
• The server trusts X-Forwarded-For only from NPM: KVITT_TRUSTED_PROXY is HA_HOST, NPM's LAN IPv4 address (an IP literal in the Pi's .env, D-125), and from that peer the server takes the last X-Forwarded-For entry as the client IP for rate limiting (D-120; the server is unchanged). A request from any other peer counts against the peer's own address.

8.6 Rate limiting and input limits

• Unauthenticated endpoints other than E-6, the web client's files (/app, /app/ and /app/*, D-136) and unknown paths: at most 60 requests per minute per client IP, then 429 rate_limited with a Retry-After header in seconds. The /app paths count against the client IP even when the request carries a bearer token (D-136): a page load is index.html and a few hashed assets that the browser then caches for a year (§15.4), so 60 per minute leaves room for reloads.
• APK downloads (E-6, GET /apk/files/{file_name}): at most 10 requests per minute per client IP, then 429 rate_limited with Retry-After. Own fixed window, not counted against the 60; every request counts, a 404 included (D-119, security review L-3).
• Authenticated endpoints: at most 600 requests per minute per device.
• Keying (D-032, revised by D-115): the per-device limit is keyed by the hash of the bearer token, with no database lookup. A token is accepted only when a response to it is 2xx. A request with a token not yet accepted counts against its client IP's unauthenticated limit before it runs and is refused with rate_limited once the IP is over; a 2xx gives that count back (a newly paired device costs its IP nothing); a 401 for an accepted token counts against the IP and withdraws the acceptance; token entries, accepted or not, are pruned once their window expires; every 401 counts against the IP exactly once (security review H-1: before, a random token answered 426 without X-Kvitt-Protocol became accepted for good, bypassed the IP limit and was never pruned). All windows are fixed from the first counted request. The client IP is the peer address, or, when the peer is the trusted proxy (KVITT_TRUSTED_PROXY, re-resolved at most every 60 seconds), the last entry of X-Forwarded-For. Per-IP keying needs the peer address: serve runs the router with into_make_service_with_connect_info::<SocketAddr>() (added by M4 in 15056dc, D-032 fulfilled).
• GET /health from the container healthcheck counts against the loopback IP's limit; at the compose healthcheck interval this stays far below 60 per minute and is accepted.
• Invite accept failures: AC-2.12.
• Card purchases (D-162, D-165): the bank's redirect GET /cards/callback (E-39) counts as an unauthenticated endpoint (60 per minute per client IP). E-37 keeps at most one pending attempt per user and provider (a new one expires the previous). E-42 contacts the bank at most once per connection per 60 seconds; a request within 60 seconds of the previous user-present fetch's start answers the current connection without contacting the bank (CP-5). Background fetches are capped at 4 per connection per 24 hours (CP-4).
• Request bodies: 1 MiB maximum, except PUT /me/picture at 5 MiB. Larger: 413 payload_too_large. Both limits are layers in router.rs (§6.3).
• JSON strings are validated for length after trimming leading and trailing whitespace, and are stored trimmed, notes included (D-034). Control characters other than newline are refused with validation_failed in notes only; this is intended. Names and descriptions accept newlines and are not checked for control characters.
• The rate limiter is in memory (resets on restart); no table.

8.7 Privacy and logging

• Server logs contain: timestamp, level, request method, route template (not the raw path with codes), status, latency, device id, error code. They never contain tokens, invite codes, display names, descriptions, notes, amounts or picture bytes.
• The phone never logs personal content, debug builds included (CLAUDE.md). Log tags use the prefix Kvitt.
• Nginx Proxy Manager's access log (proxy-host-<id>_access.log inside NPM) records the full $request_uri, query string included, on every path except /i/; the location ^~ /i/ of the Custom Nginx Configuration has access_log off and error_log /dev/null crit, so neither the invite code nor the inviter's name (?from=) reaches a log, a 502 included. NPM logs no request headers, so the Authorization token is never logged. The API's other query parameters (since, limit, size, v) hold no personal content (§10.5.2, D-120, revises D-117).
• The push sender logs one info line push sent per message with aggregates only: push_type, devices_sent, devices_targeted and the last 8 characters of each device id that got it; the per-device line is at debug (D-113).
• FCM payloads carry ids and types only (§14.6).
• Card purchases (D-161, D-163): server logs carry no merchant text, amount, date of a purchase, Enable Banking session id, account uid, authorisation code or state, and no Enable Banking response body; the card adapter logs one info line per fetch with aggregates only (card_fetch: provider id, kind background or user, the counts of new, updated and removed purchases, the HTTP status class of the bank call, and the last 8 characters of the connection id; since v0.36 also the number of bank requests, of windows split and of windows truncated (CP-7), and of pending purchases booked under their own reference (booked_by_ref) and taken over by CP-8's secondary rule (booked_by_match), D-178). /cards/callback is logged by the server under its route template only, and NPM does not log it at all (§10.5.2). The phone never logs card content (CLAUDE.md). Card data is never in a push, the audit log or GET /sync. Backups (§10.9) include the card tables in the SQLite snapshot, like every table; the private key is not in data/ and is never backed up.
• Backups on Google Drive are not encrypted in v1; they go to the owner's own Drive folder, reachable only by his Google account. The owner decided on 2026-10-19 not to encrypt them with an rclone crypt remote and to keep the token's drive scope (security review M-1 closed as an accepted risk, §8.1, docs/validation/security-review.md).

8.8 Phone hardening

• android:allowBackup="false" and android:dataExtractionRules excluding everything, so neither Google backup nor device transfer copies the token or database.
• Exported components: only MainActivity (launcher and deep-link intent filters) and library receivers guarded by a permission (Firebase's, as Firebase requires). The FCM service KvittMessagingService is not exported. Checked on the merged release manifest at M8.
• On device_revoked the app wipes local data as in AC-3.3.

8.9 Server hardening

• The server container runs as a non-root uid/gid: on the Kvitt Pi the owner's (KVITT_UID/KVITT_GID in .env, 1000:1000, D-125), on the development stack and as the image's default 10001; with a read-only root filesystem and a 16 MB tmpfs /tmp, /data as the only writable volume, its secrets read-only (the FCM key file and, since D-175, the folder secrets/cards/ with the Enable Banking private keys), no Linux capabilities, no-new-privileges.
• The TLS-terminating process is the owner's Nginx Proxy Manager on the Home Assistant Pi; its hardening is that install's, outside this repository (D-120).
• Only the server publishes a port (8080 on the Kvitt Pi's LAN; the router forwards only to NPM). The backup sidecar publishes no port and is reachable only on the compose default network. Anyone on the home LAN can reach http://<kvitt-pi-address>:8080 directly; such requests count against their own address (§8.6, D-120).
• SQLite PRAGMA foreign_keys = ON, journal_mode = WAL, synchronous = NORMAL, busy_timeout = 5000 on every connection.

---

9. Edge cases & business rules

9.1 Splits

Split modes:

split_mode	Meaning	Stored share_bp per user	Stored share_ore per user
default	The account's default ratio at the time of saving	copied from the account	computed by the ratio rule
ratio	A custom ratio for this expense	as entered	computed by the ratio rule
exact	Exact amounts for this expense	null	as entered
full	One user bears the whole amount	bearer 10000, other 0	bearer = amount, other 0

Ratio rule (modes default, ratio, full; exactly two users P = payer, N = non-payer):

share_ore(N) = floor(amount_ore * share_bp(N) / 10000)
share_ore(P) = amount_ore - share_ore(N)

The non-payer's exact share is rounded down, so the payer absorbs the remainder: the payer's share is 0 or 1 öre more than their exact share. Intermediate products are computed in 64-bit integers (the maximum, 1 000 000 000 × 10000, fits). Examples (also test vectors):

amount_ore	payer	bp payer / non-payer	share payer	share non-payer
1001	A	5000 / 5000	501	500
1	A	5000 / 5000	1	0
100	B	4000 / 6000	40	60
999	A	3333 / 6667	333	666
999	B	6667 / 3333	667	332
50000	A	0 / 10000	0	50000
50000	A	10000 / 0	50000	0

Exact rule: both shares are given, each 0 or more, and they must sum exactly to the amount, otherwise exact_sum_mismatch.

Validity: exactly two share entries, one for each household user, no other user ids; bp each 0 to 10000 and summing to 10000.

Server check: for every pushed expense the server recomputes the shares from split_mode, the amount, the payer and the given bp (or exact öre) with kvitt-domain and rejects the mutation with reason validation_failed if the pushed share_ore values differ. For mode default the server does not compare the bp with the account's current default (the phone may have copied an older default while offline); it only checks they sum to 10000.

9.2 Effect line from the viewer's side (lists)

For viewer V and an expense with payer P:

Case	Line
V = P and the other's share > 0	"You lent <other's share>"
V ≠ P and V's share > 0	"You borrowed <V's share>"
the non-payer's share = 0	"Not involved" when V ≠ P; "Paid for yourself" when V = P

9.3 Balances

For an account and user u, over non-deleted expenses and non-deleted settlements:

net(u) =   Σ expenses where payer = u            : amount_ore
         − Σ expenses                             : share_ore(u)
         + Σ settlement allocations where from = u : allocation.amount_ore
         − Σ settlement allocations where to = u   : allocation.amount_ore

• net(A) + net(B) = 0 always.
• The account balance shown to viewer V is net(V): positive " owes you net(V)", negative "You owe −net(V)", zero "All settled up" (account screens say "Settled up").
• The global balance is the sum over all accounts, archived included, deleted excluded (a deleted account has no non-deleted rows by AC-6.5).
• Balances include pending local changes.

9.4 Settlement allocation proposal

Inputs: payer user id, amount (öre, > 0), and for every non-deleted account: id, created_at, archived flag, and the payer's current net in it (computed with §9.3, excluding the settlement being edited if any).

Algorithm (normative; §14.5 has the signature):

1. Owing accounts = accounts where payer's net < 0. Sort by created_at ascending, then by id ascending.
2. remaining = amount. For each owing account in order while remaining > 0: a = min(remaining, −net), emit allocation (account, a), remaining −= a.
3. If remaining > 0 (the amount exceeds the total debt) and at least one owing account exists, add remaining to the last emitted allocation and report that account as over-settled.
4. If no owing account exists: the target is the oldest non-archived account (same sort); if every account is archived, the oldest account. Emit one allocation of the whole amount to it and report it as over-settled.
5. If there are no accounts: error no_accounts.

Output: ordered allocations, excess_ore (the amount added in steps 3 or 4, 0 otherwise), and over_settled_account_ids.

Consequences, stated so nobody "fixes" them:

• A global settle-up of exactly the global debt can leave individual accounts non-zero when the payer is owed in some account and owes in another (allocations are never negative). The global balance is then zero. Users settle individual accounts with per-account settle-ups in either direction.
• The proposal is only a suggestion; the user may edit any allocation, add accounts or remove rows.

Over-settle warning for a user-edited allocation list: allocation (account, a) is warned when a > max(0, −net_payer(account)).

Settlement validity (phone before saving, server on push): amount within §9.6; from_user_id ≠ to_user_id, both household users; 1 to 50 allocations; each amount_ore ≥ 1; account ids distinct and referencing existing non-deleted accounts; allocations sum to the amount. Error tokens in §14.5.3.

9.5 Recurring generation

• The scheduler runs once at server start and then daily at 06:00 Europe/Stockholm (DST-aware: always local 06:00). It reads the injected clock (AppState.clock) at least every 30 seconds rather than sleeping until the next run: after a forward clock jump past one or more runs it runs the missed job once; after a backward jump of more than a day it plans the next run again from the new time. The 04:00 pruning loop (§14.1) follows the same rules.
• For each template with deleted_at IS NULL and paused = 0, the candidate periods are every month p with start_period ≤ p, p ≤ end_period (if set), p > last_generated_period (if set), and whose occurrence instant (the clamped date at 06:00 Europe/Stockholm) is at or before now.
• For each candidate in ascending order the server, in one transaction: creates the expense (server-generated UUIDv7 id; expense_date = clamped date; fields copied from the template; created_by_user_id and updated_by_user_id = the template's created_by_user_id; updated_by_device_id null; created_at = updated_at = server now; recurring_template_id and recurring_period set), writes its splits (mode default resolves the account's current default ratio at generation time; other modes use the template's splits, with ratio/full recomputed by the ratio rule for the template amount), writes an audit entry (create, source = recurring), sets the template's last_generated_period and updated_at (server now), bumping its server_version, then enqueues the push (AC-9.6).
• The unique index on (recurring_template_id, recurring_period) makes generation idempotent; a conflict means the period was already generated and is skipped silently.
• Pausing stops generation. Resuming does not backfill periods whose occurrence passed while paused: on resume the server sets last_generated_period to the latest period whose occurrence instant is before now, if that is later than the current value and at or after start_period. Resuming a template that has not started yet therefore keeps its start_period (D-033).
• Changing day_of_month or start_period never regenerates past periods.
• next_occurrence_date (in the wire form, computed with kvitt-domain::next_occurrence_date, §14.5.2) is the clamped date of the first candidate period after last_generated_period that is ≥ start_period and ≤ end_period; null when paused, deleted or past end_period.
• A template's account may be archived (generation continues). Account deletion is blocked while a non-deleted template references it (AC-6.5).

9.6 Limits and validation

All string lengths are counted in Unicode code points after trimming. One table, used by phone validation and server validation alike:

Field	Rule	Error (REST) / reason (sync)
amount_ore (expense, settlement, template)	integer 1 to 1 000 000 000 (10 000 000,00 kr)	validation_failed
allocation amount_ore	integer ≥ 1	validation_failed
allocations per settlement	1 to 50	validation_failed
share_bp	integer 0 to 10000; the two sum to 10000	validation_failed
share_ore	integer ≥ 0; the two sum to the amount	validation_failed
expense description, template description	1 to 100 code points	validation_failed
expense notes, template notes	0 to 1000 code points; newlines allowed	validation_failed
settlement note	0 to 200 code points	validation_failed
expense_date, settlement_date	valid date, from 2000-01-01 to server today (Europe/Stockholm) + 365 days	validation_failed
account name	1 to 60 code points; unique (AC-6.2)	validation_failed, name_taken
category name	1 to 40 code points, or null for a default category	validation_failed
user display_name	1 to 40 code points	validation_failed
device name	1 to 60 code points	validation_failed
fcm_token (E-17)	1 to 512 characters after trimming, or null to clear; a Firebase Installation ID has 22 (D-114)	invalid_request with field fcm_token
day_of_month	integer 1 to 31	validation_failed
start_period	YYYY-MM, not earlier than 12 months before the current month	validation_failed
end_period	null or YYYY-MM ≥ start_period	validation_failed
updated_at in a push	≤ server now + 10 minutes	clock_skew
mutations per POST /sync	1 to 100; 0 is also batch_too_large (D-036)	batch_too_large
GET /sync limit	1 to 1000, default 500	invalid_request
GET /sync since	required, integer ≥ 0	invalid_request
picture upload	≤ 5 MiB, ≤ 8000 × 8000 px, JPEG/PNG/WebP	payload_too_large, image_invalid, unsupported_media_type
card history_days (E-37, E-41)	one of 7, 30, 90, 180 (CP-3; K0 reached at least 150 days right after BankID, so 180 stays, D-177); E-41 accepts only a value ≤ the current one	validation_failed
card purchase merchant (stored)	0 to 140 code points, truncated by the server (CP-7)	none (never sent by clients)
E-44 body	expense_id a non-deleted expense id or null; ignored bool; ignored true needs expense_id null; a credit purchase accepts only expense_id null and ignored false (CP-8)	validation_failed; an unknown or deleted expense_id is not_found with field expense_id; expense_already_linked
GET /cards/sync since, limit	as GET /sync: since required, integer ≥ 0; limit 1 to 1000, default 500	invalid_request

Strings are stored as validated, that is trimmed (§8.6, D-034).

On the phone, a rule of this table that has no domain error token of §14.5.3 (the length limits, the date limits, day_of_month, the periods) is reported as FieldError.error = validation_failed (§14.2.4), the same token as the REST code; a missing required value is required.

The phone input field for amounts accepts digits, one decimal separator (, or .) and at most two decimals, without sign, and converts to öre exactly (string parsing, never floating point). A stored amount opens for editing with both decimals ("1 247,60", "12 400,00"); ratio percent fields keep the trimmed form ("60", "60,5") (D-078; AmountInput.of and AmountInput.percent in :core:design).

9.7 Icon and colour tokens

Category icon tokens are Material Symbols names. The allowed set (exhaustive, 33 tokens; key, shield and account_balance added by D-054):

shopping_cart, restaurant, local_cafe, home, bolt, water_drop, wifi, directions_car, train, local_gas_station, flight, hotel, luggage, movie, music_note, sports_esports, fitness_center, medical_services, medication, shopping_bag, checkroom, pets, child_care, school, card_giftcard, celebration, build, chair, subscriptions, category, key, shield, account_balance.

Colour tokens (exhaustive, 14 tokens; slate and amber added by D-054) with the muted Kalas values of docs/ux/design-spec.md §2.3 (D-047, D-051; recorded in v0.9). The table holds the base colour of each token; design-spec.md §2.3 also gives each token's container (the colour over surface at 18 % in light, 24 % in dark) and the contrast ratios, all at least 3:1 as graphics. Category colours are never used for text.

Token	Light	Dark
green	#4E7A55	#8FB896
orange	#B26A3E	#E8AA7E
brown	#6B5244	#B8A090
yellow	#9C7C2A	#E6C67A
blue	#4A78A8	#98C0E6
teal	#367F82	#8CCAC8
purple	#865891	#C59CDA
red	#A84B45	#DC8F86
pink	#AE5D7C	#EFB0BE
grey	#6C7177	#B0B2B3
indigo	#45508D	#969DD8
lime	#73822F	#B9CC86
slate	#5E2D4E	#B0719A
amber	#937D63	#DFCFC0

The server validates icon and colour against these lists (validation_failed).

9.8 Formatting

• Money, Swedish locale: 1 234,50 kr (U+00A0 no-break space as the thousands separator and before kr; comma decimal; always two decimals).
• Money, any other locale: SEK 1,234.50 (U+00A0 after SEK; comma thousands; point decimal; always two decimals).
• Money is never shown with a minus sign; direction is in words (§9.2, §9.3).
• Dates in lists: Swedish 3 okt., English 3 Oct; with year when not the current year (3 okt. 2025, 3 Oct 2025). Detail views: Swedish lördag 3 oktober 2026, English Saturday, 3 October 2026. Timeline times: 24-hour 14:02 in both languages.
• Relative "last synced": "just now" (< 1 minute), "N min ago" (< 60 minutes), "N h ago" (< 24 hours), otherwise the list date and time. Swedish: "nyss", "för N min sedan", "för N h sedan".
• Chart axis labels (months): Swedish three-letter forms without a dot (maj, jun, … okt), English May, Jun, … Oct; list dates keep the Swedish abbreviation dot (3 okt., 25 sep.; mars, maj, juni, juli are written out) (D-065).
• Day ranges in captions and summaries (S-11 total caption, S-12 summary) are written out with the year: Swedish 24 augusti–17 oktober 2026, 1–30 november 2026, 28 december 2025–3 januari 2026 (the year once when both ends share it, the month once when both ends share it); the period chip and the S-12 title keep the short form 24 aug.–17 okt. (D-077, extends D-065; DateFormatter.dayRangeLong).
• File sizes (the update banner, S-17): SI megabytes (10^6 bytes) with one decimal rounded half up and U+00A0 before MB: Swedish 8,4 MB, English 8.4 MB (D-065).
• Month and weekday names in Swedish and English are tables inside DateFormatter, not platform locale data, so JVM tests and the phone give identical output (D-065).
• Formatting lives in :core:design (MoneyFormatter, DateFormatter), never in :domain.

9.9 Online-only actions

When the phone has no validated network (Android NET_CAPABILITY_VALIDATED) or the last request failed with a network error less than 30 seconds ago, these actions are disabled with "Needs connection" ("Kräver anslutning", common_needs_connection): create, edit, archive, unarchive, delete of accounts, categories and recurring templates; profile name and picture; invites; device revoke; in-app update; "Sync now" ("Synka nu") on S-8 and S-10 (their missing states) and on S-16 (D-080); and for card purchases (D-162, D-165): connecting and renewing (S-25, "Förnya med BankID"), "Uppdatera" on S-23, the history setting and "Koppla från" on S-26. Linking, unlinking, ignoring and "Skapa utgift" are not online-only (CP-9); pull to refresh on S-23 ends at once offline, as on S-4. A REST call that fails with a network error shows "Could not reach the server" and changes nothing locally. Pull-to-refresh on S-4 and S-5 is not disabled offline; it ends at once without a sync (D-127).

9.10 Other edge cases

Situation	Rule
Both users edit the same expense offline	Last updated_at wins; the loser's phone receives stale with the winner's row, overwrites locally and lists it under "Changes not synced" (§14.4.6). Both edits are in the audit log only if both were accepted, so only the winning edit is logged.
One user deletes, the other edits the same expense offline	Delete wins regardless of arrival order and timestamps: a pushed delete is always applied, and any non-delete write to a tombstoned row is rejected deleted (§14.4.4).
An expense is created offline in an account that was deleted meanwhile	Rejected reference_not_found; the row is removed locally and listed under "Changes not synced". Cannot happen for archived accounts (writes to archived accounts are accepted).
An expense uses a category that was archived meanwhile	Accepted.
Phone clock far in the future	Pushes rejected clock_skew; the app shows "Your phone's clock is wrong" on the sync status screen and keeps the changes pending.
Phone clock behind	Its edits may lose LWW against older real edits. Accepted risk.
Server restored from an older backup	The server's sync_epoch changes (§10.9); phones detect it and re-push everything they hold (§14.4.8), so changes made after the backup are recovered from the phones.
Partner never joins	Admin stays in the waiting state (AC-5.1).
Admin loses phone	kvitt-server pair-device --user <admin id> on the Pi (AC-1.6); then revoke the lost device from the new phone.
Both users' devices revoked	Same recovery as above for each user.
An account is renamed to a name used by a deleted account	Allowed (uniqueness ignores deleted accounts).
Recurring template's category deleted	Cannot happen: category deletion is blocked while a template uses it.
Expense amount edited in mode exact	The editor keeps the typed user's share and recomputes the other; if the typed share now exceeds the amount, saving is blocked (AC-8.7).
Settlement edited so that an allocation's account was deleted meanwhile	Cannot happen: an account with allocations cannot be deleted.
Same user on two devices edits offline	Same as two users: LWW per row.
Time zones	Dates (expense_date, settlement_date) are calendar dates chosen by the user; analytics never convert them. Only "today" defaults use the phone's zone; server validation and scheduling use Europe/Stockholm.
A day with a DST change	Scheduling uses local 06:00, which exists on every day in Europe/Stockholm.

9.11 Category suggestion

The expense editor (S-7) selects the category from the description while the user types (D-049, owner 2026-10-18). The rule is a pure function in :domain (§14.5.6, with platform Unicode services through UnicodeText), fed by ExpenseRepository.suggestCategory in :data (§14.2.4) from Room and the keyword table contracts/category-keywords.csv (§14.8).

CS-1 Scope. The suggestion runs only in the editor for a new expense. It never runs when an existing expense is edited and never changes the category of a saved expense. The recurring template editor (S-19) does not use it in v1.

CS-2 Manual choice wins. The editor keeps a flag "category picked by hand", false when the editor opens. Picking any category in the category grid sets it to true, also when the user picks the category already shown. While the flag is true the suggestion never changes the category, for the rest of this editor session (until the editor closes). Nothing resets the flag.

CS-3 When it runs. While the flag is false, the category is recomputed on every change of the description and on every change of the account. It is a local computation over Room data; no network.

CS-4 Normalisation. Descriptions (typed and stored) and keywords are compared after this normalisation:

1. Unicode NFC, then lowercase without locale rules (Kotlin lowercase(), which uses Locale.ROOT).
2. Delete every ' (U+0027), ’ (U+2019) and : (so "Willy:s" becomes "willys" and "McDonald's" becomes "mcdonalds").
3. Replace every remaining code point that is not a Unicode letter (general category L), a decimal digit (general category Nd) or & with a space. Whitespace is therefore replaced too.
4. Collapse runs of spaces to one space and trim.

Diacritics are kept (å, ä, ö and é stay distinct; the keyword table lists both spellings where it matters). Digits are kept. The tokens are the normalised description split on spaces; the first token is the first of them. An empty normalised description matches no history and no keyword.

CS-5 Order. The suggested category is the first that applies of:

1. History, exact: among the non-deleted expenses on the phone (every account, either user, pending, imported and recurring ones included) whose normalised description equals the normalised typed description, the category used most often; on a tie, the one used most recently.
2. History, first token: among the non-deleted expenses whose first token equals the typed description's first token, the category used most often; on a tie, the one used most recently.
3. Keywords: the category of the winning entry of the keyword table (CS-6).
4. Default: the AC-8.6 fallback: the category last used in the selected account on this phone if still active, else other; when other is archived too, no category (AC-8.6).

"Used most often" counts the matching expenses per category. "Most recently" compares the latest matching expense of each tied category by (expense_date, then created_at), the expense-list order of AC-8.10; if that still ties, the lower category id (string order) wins. Archived and deleted categories are left out of the count; when no category is left, the next step applies (owner, 2026-10-18: most often, not most recent).

CS-6 Keyword table. Each entry has a keyword (already normalised per CS-4), a match and a default_key. An entry matches when:

• token: some token equals the keyword;
• prefix: some token starts with the keyword;
• phrase: the keyword's tokens occur consecutively in the tokens.

When several entries match, the longest keyword (in code points, spaces included, a surrogate pair counting as one) wins; on equal length, the entry earlier in the table wins (the table is sorted by default_key, then keyword, both in code-point order). The winning entry gives the active category with that default_key (a renamed default included, since the key stays). If that category is archived, the next matching entry in the same order is tried; when none is left, step 4 applies. The table is fixed data shipped with the app; users do not edit it. No entry maps to other.

CS-7 What the user sees. The suggestion simply replaces the category shown in the Kategori field: no caption, no marker, no confirmation (owner, 2026-10-18: a wrong guess is corrected with one tap). Clearing the description returns the field to the step-4 default.

Evidence (D-049): a chronological replay of the household's 1 775 Splitwise expenses with the fourteen categories of AC-7.2 and the §10.8 mapping put 79.7 % of rows in the right category, against 30.5 % for the step-4 default alone; with no history, the keywords cover 77 % of rows at 96 % accuracy. The replay is in docs/ux/category-suggestion.md.

9.12 Card purchases (D-158 to D-176)

The rules of FR-22. The card holder is the user who connected the card; "purchase" is one card transaction as the bank reports it. Facts about the provider (established 2026-10-24, D-159): the SJ Prio Mastercard is issued by SEB Kort Bank AB and, as a payment account, is reachable through PSD2 account information (AIS): read only, no payments. Kvitt reaches it through Enable Banking (enablebanking.com), whose changelog (August 2024) lists an "SJ Prio Mastercard (SE)" integration, in its restricted production mode: free, for evaluation and individual non-commercial use, fetching data only from accounts linked to the application in Enable Banking's control panel ("Activate by linking accounts", done with the bank's own authorisation, BankID). PSD2 RTS Art. 36(5)(b): without the user actively requesting it, a provider may access an account at most 4 times per 24 hours. Since the 2023 RTS amendment, access through a provider needs a renewed strong customer authentication (BankID) at most every 180 days; the bank's maximum_consent_validity may be lower. History older than about 90 days is usually available only right after authentication. The spike K0 measured the owner's card on 2026-10-24 (PLAN-K0, report docs/spikes/K0-enable-banking.md, D-177); its results are stated in the rules below as measured ("K0: …"). Three points were not measured and rest on the owner's decision of 2026-10-24 ("let's just assume it all works now given your test", D-177): the partner's card links to the owner's application (CP-13), a pending transaction keeps its entry_reference when it is booked (CP-8), and a session is reused on later days without BankID (CP-6). K1's owner steps verify all three on the real server (PLAN-K1 §8).

CP-1 Catalogue (D-160). Supported cards are entries of a provider registry in kvitt-server (src/cards/providers.rs), served by E-36. Each entry has an open-string id, a display name, the issuer, the Enable Banking ASPSP name and country, an image key and its source adapter (enable_banking); nothing outside the adapter names the vendor, and ids are never enums (CLAUDE.md). The registry has one entry: id sj_prio_mastercard, name "SJ Prio Mastercard", issuer "SEB Kort", ASPSP name SJ Prio Mastercard, country SE, image key sj_prio_mastercard (K0: listed exactly so in GET /aspsps?country=SE, one of 126 Swedish ASPSPs, beta false, psu_types [personal], auth method REDIRECT). The app and the web map the image key to their bundled artwork, committed in both (D-180); an unknown key draws the fallback card. A user has at most one connection per provider (D-167).

CP-2 Connecting (D-162). E-37 creates an authorisation attempt for the caller (user and device), the provider, the chosen history and the client (android or web): a random 32-byte state (base64url, stored only as its SHA-256 hash, like invite codes, §8.3), status pending, expiry 15 minutes after creation. It calls Enable Banking POST /auth with access.valid_until (CP-6), the ASPSP, the state, redirect_url = <KVITT_PUBLIC_URL>/cards/callback and psu_type personal, and returns the attempt id, the bank URL and the expiry. A new attempt for the same user and provider expires a pending older one. The client opens the URL (Android: a Custom Tab, D-173; web: the same tab, D-174); the user signs with BankID (app-to-app on the phone, QR in a desktop browser). The bank redirects the browser to E-39 with code and state (or error). E-39 looks the attempt up by the hash of state (D-184): an unknown or already used state changes nothing and shows the failure page; an expired one stores the attempt as expired and shows it too; otherwise the attempt is claimed atomically (only one callback gets past this point) before Enable Banking is asked for anything; then an error marks it failed with cancelled, a callback with neither code nor error failed with bank_error, and with a code it calls Enable Banking POST /sessions with the code, picks the card account (exactly one account in the session: that one; several: the first whose cash_account_type is CARD, else the first; none: failed with no_account, and that session is revoked at Enable Banking, best effort, D-184; K0: the SJ Prio session holds exactly one account, currency SEK, cash_account_type CARD), creates or updates the user's connection for that provider (status active, the new session id, account uid, valid_until, history), marks the attempt connected, starts the first fetch in the background (CP-4, user present with the callback request's address and user agent) and shows the success page. The attempt is single use: a second callback with the same state shows the failure page and changes nothing. The pages (bilingual by Accept-Language, copy in §13.3 "Card callback page") link back to the client: kvitt://cards/connected?attempt=<attempt id> for android, /app/cards?attempt=<attempt id> for web. The page never redirects by itself (a browser may block a scripted jump to kvitt://); the client learns the result by polling E-38 every 2 seconds while its connect screen is open (S-25, W-22) and when the return link opens it. Renewing an existing connection (CP-6) is the same flow; on success the connection keeps its id and every purchase, and the previous session is revoked at Enable Banking (best effort).

CP-3 History (D-164). The connect screen offers "Hämta köp från de senaste 7 / 30 / 90 / 180 dagar", default 30 days. The first fetch after an authorisation asks for transactions of that many days up to today (Europe/Stockholm), today counted as one of them (date_from = today − (history_days − 1), D-181), in windows (CP-7). K0: right after BankID the card gave at least 150 days (five consecutive 30-day windows back to 150 days, all answered with rows; the last 30 days to 180 were not asked by window), so 180 stays offered (D-177). The setting can be shortened later (E-41; it only affects later renewals, stored purchases stay); a longer value needs a fresh BankID, so S-26 offers it only through "Förnya med BankID" (E-37 with the new value), and says so ("En längre period kräver BankID igen").

CP-4 Background fetch (D-165). Enable Banking's FAQ: "many ASPSPs have the limit of 4 times a day for data fetches when PSU is not online". The server fetches every active connection in the background at 06:45, 11:45, 16:45 and 21:45 Europe/Stockholm (four slots spread over the day, away from the 04:00 pruning and the 06:00 recurring run), without the user's headers (not user present). A slot is skipped when the connection started 4 background fetches in the preceding 24 hours (background_fetches, the start times of the last four), when any fetch for it succeeded less than 2 hours before, or when one is running. The scheduler reads the clock as §9.5 does; after downtime it runs at most the slot that is due, never a backlog: at start-up the latest slot already passed runs once, subject to the 4-per-24-hours quota and the 2-hour rule (D-185). Every background start counts towards the quota, whatever its outcome (D-185). K0: a fetch without the user's headers was accepted for the SJ Prio card (HTTP 200); how many the bank accepts per 24 hours was not measured, so the 4-per-24-hours rule stands. A background fetch normally makes one bank request (its range starts 10 days before the latest stored booking date, one window of CP-7); the card_fetch line counts the requests (§8.7).

CP-5 User-present fetch (D-165). "Uppdatera" and pull to refresh on S-23 (and "Uppdatera" on W-21) call E-42, which fetches with the user present, so it does not count as background access. Enable Banking's PSU headers are Psu-Ip-Address, Psu-User-Agent, Psu-Referer, Psu-Accept, Psu-Accept-Charset, Psu-Accept-Encoding, Psu-Accept-language and Psu-Geo-Location, and a fetch sends "either all required PSU headers (in case of online data fetching) or none", the required set being the ASPSP's required_psu_headers in GET /aspsps. A user-present fetch therefore sends Psu-Ip-Address (the client IP of §8.6, which the rate limiter puts in a request extension for this, D-188) and Psu-User-Agent always, plus every other header the ASPSP requires, each taken from the app's own request (User-Agent, Referer, Accept, Accept-Charset, Accept-Encoding, Accept-Language); Psu-Geo-Location is never sent (Kvitt has no location). Each header is sent only when the app's request carries a value for it (D-186). The ASPSP's details from GET /aspsps are cached for 24 hours; when /aspsps fails, only Psu-Ip-Address and Psu-User-Agent are sent (D-186). K0: the SJ Prio ASPSP's required_psu_headers is exactly [psu-ip-address]; Enable Banking lists the names in lower case, so they are compared case-insensitively; a fetch with Psu-Ip-Address and Psu-User-Agent was accepted (HTTP 200) from the MacBook, and from the Pi it is checked by K1's owner steps. A background fetch sends none. E-42 contacts the bank at most once per connection per 60 seconds (§8.6) and waits up to 25 seconds for the fetch; if it takes longer it answers with fetching true and the fetch completes in the background. The app then pulls E-40. On the phone the regular sync triggers (AC-15.3) also pull E-40, so purchases fetched in the background reach the phone without a tap.

CP-6 Consent (D-166). access.valid_until asks for now plus the smaller of 180 days and the ASPSP's maximum_consent_validity (given in seconds in GET /aspsps), less 5 minutes (K0: the SJ Prio value is 15552000 seconds, 180 days, so the request is now plus 180 days less 5 minutes; the session made on 2026-10-24 returned valid_until 2027-04-22); the stored valid_until is the one Enable Banking's session returns. The session serves every fetch, user-present and background, until then without a new BankID (owner's assumption, D-177; K0 did not repeat a fetch on a later day, K1's owner steps check it). From 14 days before it, S-23 and S-26 show the expiry notice with "Förnya med BankID"; once it has passed, or Enable Banking reports the session expired or revoked, the connection's status becomes expired: no fetch runs, the stored purchases stay and keep working (link, ignore), and "Förnya med BankID" renews (CP-2).

CP-7 Incremental fetch and mapping (D-168, D-178, D-179). Each fetch covers the range from date_from = the later of (today − (history_days − 1), today being one of the history_days days, D-181, revising the earlier "today minus history_days", which made 181 days and 7 windows for 180) and (the latest stored booking date of the connection minus 10 days) up to today, so a purchase booked late and a pending purchase turning booked are seen again; the first fetch after an authorisation starts at today − (history_days − 1). K0: the SJ Prio card answers every transactions request with at most 100 transactions and never a continuation_key, so a longer range loses rows without an error (90 days gave 100 rows covering only the newest 60 days; 180 days with strategy=longest gave 100 rows that were neither the newest nor a contiguous range). The range is therefore fetched in windows (D-178):

• Windows: consecutive, non-overlapping, at most 30 days each, newest first, each asked with date_from and date_to (both inclusive); the oldest window takes what is left and may be shorter. A first fetch of 180 days makes 6 requests; an incremental fetch (10 to about 20 days) makes 1. A continuation_key, if one is ever returned, is followed within its window.
• Split: a window whose response holds 100 or more transactions (the cap, so the response may be cut) is split into two halves, the newer half taking the extra day of an odd length, and each half is asked again, newest first, down to windows of one day; the rows of the cut response are discarded and only the halves' rows are kept (D-185). A one-day window that still holds 100 is kept as returned and counts as truncated.
• strategy is never sent (Enable Banking's default strategy): strategy=longest neither lifts the cap nor returns the newest rows.
• WRONG_TRANSACTIONS_PERIOD for a window (not seen in K0) means the bank has no older history: that window and every older one are skipped and the fetch succeeds with the newer windows; the deletion of vanished pending purchases (CP-8) then covers only the windows that answered (D-185).
• A window may return transactions whose booking date lies one or two days outside it (K0: the bank filters on another date), so every transaction is kept as returned and the transactions of all windows are de-duplicated by provider_ref (below) before CP-8; the first occurrence, from the newer window, wins.
• Any other error ends the fetch with CP-14's error; the transactions of the windows already fetched are applied (CP-8).
• A fetch is complete when every window of its range answered and none was truncated; only a complete fetch deletes vanished pending purchases (CP-8).

Each transaction maps to a purchase:

• provider_ref: the transaction's entry_reference, which Enable Banking documents as "unique and immutable" but "in most cases … provided only for booked transactions" (transaction_id "may change" and is not used). K0: on the SJ Prio card it is on every transaction, the pending ones included, unique, and unchanged between two fetches. When absent, h: + lowercase hex SHA-256 of <purchase_date>|<amount>|<indicator>|<merchant text>|<n>, <n> the 0-based index of an identical earlier transaction in the same window's response.
• direction: debit for DBIT, credit for CRDT. status: pending for PDNG, booked for BOOK; other statuses are skipped. bank_transaction_code is not used: the direction alone decides (D-179). K0 saw PURCHASE 92, PAYMENT 5, UNKNOWN 2 and FEE 1 in 100 transactions; a debit FEE (a card fee) or PAYMENT is a debit like any purchase, so it is "Att hantera" and the holder turns it into an expense or ignores it.
• purchase_date: booking_date, else value_date (a pending transaction has no booking date), else transaction_date; a transaction with none of the three is skipped. booking_date is stored when the transaction is booked. K0: value_date on every transaction, booking_date on every booked one and on no pending one, transaction_date on none (D-179).
• Amount: transaction_amount.amount is a decimal string parsed to öre exactly (string parsing, never floating point, as §9.6's amount input); its sign is ignored, the direction carries it. K0: positive decimal strings with a point, and every transaction in SEK, purchases at German, Irish and Estonian merchants included (exchange_rate empty): the card account reports foreign purchases converted to SEK. A transaction whose currency is not SEK (not seen in K0; kept as a safeguard) is stored with amount_ore null, its amount as the decimal string original_amount and original_currency (ISO 4217); such a purchase shows " " with "Utländsk valuta", gets no matches (CP-10) and "Skapa utgift" opens S-7 with the amount empty. A transaction of 0,00 is skipped.
• merchant: the remittance_information lines joined with a space, else creditor.name, else "Kortköp" ("Card purchase"); whitespace collapsed, trimmed, at most 140 code points (truncated). K0: remittance_information holds exactly one line on every transaction and it is the merchant text; creditor.name is never present (D-179).
• Nothing else of a transaction is stored, logged or sent to a client (D-179): in particular not debtor.name (K0: the card holder's name), debtor_account (K0: a masked card number, scheme CPAN), creditor.postal_address (K0: the merchant's country and town), transaction_id or bank_transaction_code.

CP-8 Matching a fetch to stored purchases (D-168, D-177). Within one connection: a transaction whose provider_ref is stored updates that purchase's status, dates, amount and merchant (link and ignore state kept). On the SJ Prio card a pending transaction carries an entry_reference (K0), and a pending transaction is assumed to keep it when it is booked (owner's assumption, D-177; K1's owner steps check it through booked_by_ref and booked_by_match, §8.7), so the booked transaction updates the pending purchase by its reference. The secondary rule, for a booked transaction with no stored provider_ref (a bank that gives the booked transaction a new reference, or a pending one stored under the fallback hash), takes over a stored pending purchase of the connection (its id, link and ignore state kept; its provider_ref replaced) when the amounts and directions are equal, the dates are at most 3 days apart and the CS-4 first tokens (§9.11) of the merchant texts are equal (the server takes the first token with Rust's standard Unicode character classes and without NFC normalisation: it only compares two texts from the same bank, D-182); among several, the oldest pending one. Otherwise it is a new purchase. After a complete fetch (CP-7), a stored pending purchase dated inside the fetched range that the bank no longer reports, neither linked nor ignored, is deleted (a tombstone with its content erased, D-167); a linked or ignored one stays as it is. Credit purchases (credit: refunds, deposits, the card bill's payment; K0: 2 of 100 transactions, both payments of the card bill, no refund) are stored but never "Att hantera": they show only under "Alla", marked "Insättning", with no actions, because §9.6 has no negative expense; the sheet says to change the original expense by hand.

CP-9 Turning a purchase into an expense (D-169). "Skapa utgift" opens S-7 (W-5 on the web) as a new expense prefilled with: amount = amount_ore; description = the merchant text, trimmed to 100 code points (§9.6), case unchanged; date = purchase_date; payer = the card holder (the viewer); account = from S-27 the account it was opened from, otherwise the AC-8.6 default (the account last used on this phone, or browser, if still active, else the oldest active account); category = the §9.11 suggestion for that description and account (it is a new expense, CS-1; the user's own pick wins, CS-2); split mode default; notes empty. Saving creates an ordinary household expense (sync push, audited, the partner is notified as for any expense) and links the purchase to its id. A purchase links to at most one expense, and an expense is linked from at most one purchase of each user (expense_already_linked). "Ta bort koppling" (S-23 sheet, S-8) clears the link; the expense stays. When a linked expense is deleted, by either user, the server clears the link in the same transaction (§14.4.4 step 7), so the purchase is "Att hantera" again; the phone clears it locally at its own delete. On the phone, link, unlink and ignore are written to the local copy at once (offline too) and sent with E-44 after the household push of the next sync cycle, so the expense exists on the server first (§14.4.5, D-173); the web sends E-44 at once. The link is not audited and not pushed; editing the expense later leaves the link.

CP-10 Suggested matches (D-170). For a debit purchase in SEK that is neither linked nor ignored, the matches are the household's non-deleted expenses (either user's, imported and recurring included) with amount_ore equal to the purchase's, expense_date within 3 days before or after purchase_date, and not linked from another purchase of the viewer; ordered by the absolute day difference, then created_at descending, then id; at most 3 shown. Computed on the phone from Room and in the browser from the snapshot by the pure function matchCardPurchase (§14.5.8, vectors match_card_purchase.json). A row with exactly one match shows the chip "Koppla till "; with two or three, " möjliga utgifter", which opens the sheet. "Välj en annan utgift" in the sheet lists the non-deleted expenses not linked from another purchase of the viewer, dated within 14 days of the purchase, any amount, newest first.

CP-11 Privacy (D-161). Owner, 2026-10-24: only the card holder sees their card purchases. Card connections and purchases are read and written only by their holder's devices; every other caller, the other user's devices included, gets not_found for their ids, the same as an unknown id (cf. D-156). They are not in GET /sync, not audited, not pushed, not in S-11, S-12, E-34 or E-35, and the partner's phone stores none. An expense created from a purchase is an ordinary household expense; only the holder sees that it came from a card (S-8, AC-22.10).

CP-12 Disconnecting (D-167). E-43 revokes the session at Enable Banking (DELETE /sessions/{id}, best effort: a failure is logged without the id and the disconnect goes on), sets the connection's status to disconnected and erases its session id and account uid, and deletes the connection's purchases that are neither linked nor ignored (tombstones with their content erased). Linked and ignored purchases stay (the user's decisions, which keep a later reconnect of the same card from offering them again) unless erase_handled is true, when they are deleted too. Expenses created from purchases stay. Connecting the same card again reuses the connection (one per user and provider).

CP-13 Server configuration (D-175). Enable Banking's production control panel accepts only https redirect URLs (an http://localhost URL "uses unsupported scheme"); the application's registered redirect URL is https://<KVITT_PUBLIC_HOST>/cards/callback, the path of E-39, and no other is needed. The application id is not a secret but is kept out of the repository's text (it is the configuration's value, §10.4, and the key file's name in K0's git-ignored folder). Card features need an Enable Banking application: an application id and its private key file (§10.4). One application may serve both users (the owner links both cards to it in Enable Banking's control panel) or each user has their own. The owner's application exists (K0: restricted production, activated by linking the owner's card, its key file in K0's git-ignored folder until K1's owner steps copy it to the Pi). The partner's card is assumed to link to the owner's application (owner's assumption, D-177; K0 did not try it, K1's owner steps do); the fallback is the partner's own application, which KVITT_EB_MEMBER_APP_ID and its key file configure without code change. A user without a configured application sees the provider as not available (E-36 available false, AC-22.1); E-37 answers cards_unavailable. The owner accepts Enable Banking's Terms of Service before an application exists (the licence step of CLAUDE.md, PLAN-K0).

CP-14 Errors (D-165). A fetch that fails records last_fetch_error on the connection: bank_unavailable (Enable Banking or the bank did not answer, or answered 5xx), rate_limited (the bank refused for too many requests), consent_expired (CP-6) or failed (anything else); a later successful fetch clears it. Enable Banking's answers map as follows (D-183): EXPIRED_SESSION, CLOSED_SESSION, REVOKED_SESSION and SESSION_DOES_NOT_EXIST → consent_expired, and the connection's status becomes expired (CP-6); ASPSP_RATE_LIMIT_EXCEEDED or HTTP 429 → rate_limited; ASPSP_ERROR, ASPSP_TIMEOUT, HTTP 408, any 5xx or no answer → bank_unavailable; WRONG_TRANSACTIONS_PERIOD is no error but ends the walk back (CP-7); anything else → failed. S-23 shows "Kunde inte hämta köp. Senast uppdaterad " while it is set, except for consent_expired, which shows the expired state.

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10. Deployment & ops

All infrastructure files live in infra/ (ownership §14.7). Secrets live in infra/secrets/ on the Mac (git-ignored) and in ~/kvitt/secrets/ (/home/jacobhagstedt/kvitt/secrets/) on the Pi (D-125); neither is ever committed.

Development first (D-001). During development the server runs locally on the owner's M4 Mac (Docker compose from infra/dev/compose.yaml, or plain cargo run in server/), and debug builds pair against it over the home Wi-Fi (debug builds accept http:// to private LAN addresses, AC-2.8). The development stack (built by M2c-dev, landed c885aba, D-022) has the server service and the backup job runnable on demand without the Drive upload; it has no proxy and no TLS (plain http://, which debug builds accept on private LAN addresses). Its data is a bind-mounted folder on the Mac (infra/dev/data/, git-ignored, and infra/dev/backups/ for local snapshots); it mounts infra/dev/secrets/ (git-ignored) read-only at /secrets, into which infra/dev/up.sh copies only fcm-service-account.json from infra/secrets/, so the server container sees no other secret (D-117; a folder rather than the file, so a missing key leaves the folder empty and push disabled, §10.4); its env file is infra/dev/.env.example (no RCLONE_REMOTE since fc6126c: the development backup never uploads); its server healthcheck is kvitt-server healthcheck; its backup runs as uid 10001 so that it can open the WAL files the server owns (on the Pi both run as the owner's uid, D-125). The Pi's env template is infra/pi/.env.example (D-103, D-125). The development stack's database was migrated to schema 2 (migration 0002, §14.1.1) on 2026-10-18 after a backup, and to schema 3 (migration 0003, §14.1.2) on 2026-10-18 when it was rebuilt from b7b7483, again after a backup. On the Mac's Podman setup infra/dev/up.sh alone does not swap in a rebuilt image: run infra/dev/up.sh --down, then infra/dev/up.sh. Firebase (§10.7) is set up during development because push is needed then. Everything in this section that concerns the Pi (the Pi hosts and router of §10.1, §10.2, the registry and Pi deploy of §10.3, §10.5 TLS, publishing to the Pi in §10.6, the Drive upload of §10.9) is built by milestone M2c-pi, which runs after M8 and before M10.

No SSH from the Mac to the Pis (D-100, revises D-023). M2c-pi delivers a self-contained compose project in infra/pi/ (D-125, revises D-103): compose.yaml, the env template .env.example and a .gitignore, with the owner's checklist in infra/README.md "Pi: what the owner does" (seven steps) and the restore runbook infra/RESTORE.md. The owner fills infra/pi/.env on the Mac, copies compose.yaml, .env and secrets/ to /home/jacobhagstedt/kvitt (~/kvitt) on the Kvitt Pi and runs plain docker compose commands there; nothing on the Pi outside that folder is installed or changed, there is no install script and no script on the Pi at all, and Docker and the registry trust are prerequisites (D-125, owner decision 2026-10-20). Agents never connect to the Kvitt Pi, the Home Assistant Pi, Gitea or Google Drive and need no allowance for them; they check the project on the Mac (docker compose config with the env template, shellcheck on the scripts under infra/, a Podman rehearsal). Where §10.2 to §10.10 name a command on the Pi, the owner runs it in ~/kvitt. M2c-pi runs as the last step before M10, after the app is proven on the phone against the development server. D-001 stands: development stays on the Mac. History: the first bundle landed on 2026-10-18 (2476667, D-103 to D-106: install, deploy, bootstrap, backup and APK scripts under /opt/kvitt); since D-120 (d05f13a, 62f5279, landed with 9231a1d on 2026-10-19) TLS terminates in the owner's Nginx Proxy Manager on the Home Assistant Pi (no Caddyfile, no Caddy, no cert-sync); since D-125 (6e5981d, 2026-10-20) the scripts install.sh, deploy.sh, bootstrap.sh, backup-now.sh, install-apk.sh and lib.sh are removed and their equivalents are the compose commands of §10.6, §10.9 and §10.10. Step 4 of the checklist sets up the NPM proxy host (§10.5).

10.1 Hosts and network

Host	Role	Facts
Kvitt Pi	Runs the compose stack; publishes the server's port 8080 on the LAN for NPM (D-120)	Raspberry Pi 3, 1 GB RAM, 64-bit Raspberry Pi OS Lite (Debian bookworm or later), Docker Engine with the compose plugin (from Docker's Debian arm64 apt repository, D-104; a prerequisite, already installed, usable without sudo by the owner's user jacobhagstedt, uid and gid 1000, D-125), static LAN address. Kvitt runs from /home/jacobhagstedt/kvitt (D-125). LAN address <kvitt-pi-address>, known to the owner (OQ-3, D-100; no .env key since 200c99f); also NPM's Forward Hostname / IP; no agent and no Mac script reaches it over SSH. Outbound HTTPS from the server container to oauth2.googleapis.com and fcm.googleapis.com (push) and, since D-175, to the Enable Banking API api.enablebanking.com (card purchases); nothing inbound but NPM's forward
Home Assistant Pi	Runs the owner's Nginx Proxy Manager (NPM), which owns ports 80/443: terminates TLS for the Kvitt host name (KVITT_PUBLIC_HOST, owner-chosen, recorded in HANDOFF) with NPM's own Let's Encrypt certificate (HTTP-01 on port 80) and forwards plain HTTP to <kvitt-pi-address>:8080 (§10.5, D-120); closes every request from outside the home LAN without the app key (§8.5, D-126)	Its LAN IPv4 address is HA_HOST in the Pi's .env, filled by the owner (OQ-3), and is the server's KVITT_TRUSTED_PROXY. NPM is also the proxy host for Home Assistant under icehack.asuscomm.com, on the same port 443, and selects the proxy host by name, so Kvitt has its own name (D-124). The owner sets up the proxy host in NPM's web UI (§10.5.1); nothing of Kvitt runs there and nothing connects to it over SSH
Owner's M4 Mac	Builds release APKs (infra/publish-apk.sh); builds images only as the fallback of the Gitea workflow (infra/build-images.sh, D-104); runs the development server (D-001)	Apple Silicon, so linux/arm64 builds run natively in Docker
Router (ASUS)	icehack.asuscomm.com DDNS (Home Assistant's name); the Kvitt host name (KVITT_PUBLIC_HOST, owner-chosen; currently kvitt.suorra.duckdns.org, HANDOFF) points at the same public address (a subdomain of the owner's DuckDNS family domain suorra.duckdns.org)	External TCP 443 → Home Assistant Pi 443 (NPM), already in place for Home Assistant, serves Kvitt too: no new rule (D-124; the owner confirmed the 443 forward, 2026-10-19); external 80 already reaches NPM for Let's Encrypt; nothing is forwarded to the Kvitt Pi (D-120)
Container registry	Holds Kvitt images	A Gitea instance on another Pi at http://gitea.lan: plain HTTP, reachable only on the home Wi-Fi (D-001). Kvitt images live under the owner path gitea.lan/jacobh2 (D-104); Gitea Actions builds them (§10.3). Pushes use the Gitea secret kvitt_cicd (§10.3). The Kvitt packages are public, so the Pi pulls anonymously; were they private, the owner runs docker login gitea.lan once on the Pi with a read:package token (HUMAN, D-125). Agents never hold credentials (D-100)

The Kvitt Pi's compose stack never builds anything. It only pulls images and runs them.

10.2 Compose stack

File infra/pi/compose.yaml (compose project name kvitt). The owner copies it with .env (from infra/pi/.env.example) and secrets/ to /home/jacobhagstedt/kvitt (~/kvitt) on the Kvitt Pi, a self-contained compose project: every path in it is relative to that folder and nothing outside it is installed or changed (D-125, revises D-103; until then install.sh installed the stack to /opt/kvitt). The folder holds compose.yaml, .env, secrets/ (fcm-service-account.json, rclone.conf) and the bind-mounted folders data/ (SQLite, pictures, data/apk/), backups/ and import/, which the owner creates before the first start (mkdir -p data/apk backups import; and mkdir -p secrets/cards && chmod 700 secrets/cards since K1, D-188), because a bind-mount source that Docker creates itself belongs to root and the containers cannot write to it. Services:

Service	Image	Ports / volumes	Memory limit	Healthcheck
server	${KVITT_REGISTRY}/kvitt-server:${KVITT_TAG}, command serve	./data:/data; ./secrets/fcm-service-account.json at /secrets/fcm-service-account.json, read-only, create_host_path: false; ./secrets/cards at /secrets/cards (the Enable Banking private keys, D-175), read-only, create_host_path: false (an empty folder disables card features, but a missing one stops docker compose up, even with no card configured: the folder must exist from K1's image on, D-188); environment also KVITT_EB_APP_ID=${KVITT_EB_APP_ID:-} and KVITT_EB_MEMBER_APP_ID=${KVITT_EB_MEMBER_APP_ID:-}; ./import:/import:ro (empty except during the one-off import, §10.8, D-025); publishes 8080:8080 on all of the Kvitt Pi's interfaces (NPM connects over the LAN, D-120); environment TZ, KVITT_DATA_DIR=/data, KVITT_PUBLIC_URL=https://${KVITT_PUBLIC_HOST} (port 443, D-124), KVITT_TRUSTED_PROXY=${HA_HOST}; the other settings keep their §10.4 defaults	160 MiB (budget: RSS under 100 MB in steady state)	kvitt-server healthcheck, the binary's own GET http://localhost:8080/health (no curl in the image); every 30 s, timeout 5 s, 3 retries, start period 20 s
backup	${KVITT_REGISTRY}/kvitt-backup:${KVITT_TAG}	./data:/data; ./backups:/backups; ./secrets/rclone.conf at /config/rclone/rclone.conf, read-only, create_host_path: false; environment TZ, HOME=/tmp, RCLONE_REMOTE=gdrive: (fixed in compose.yaml, the [gdrive] remote of rclone.conf), RCLONE_FOLDER_ID=${RCLONE_FOLDER_ID}	96 MiB	/healthcheck.sh: last successful run marker newer than 26 hours, or no run yet since start; every 5 min, start period 30 s

• No named volumes: data and backups are the bind mounts ./data and ./backups (D-125; were the named volumes data and backups; certs and caddy_data were removed by D-120).
• Both services: user: "${KVITT_UID}:${KVITT_GID}", the owner's uid and gid (1000:1000 on the Pi); read_only: true with a 16 MB tmpfs /tmp; cap_drop: [ALL]; no-new-privileges; restart: unless-stopped; logging driver json-file with max-size: 10m, max-file: 3; TZ=Europe/Stockholm.
• The compose default network (no network is declared; was the bridge network kvitt); only server publishes a port.
• No host firewall limits the published port 8080 to HA_HOST, so any device on the home LAN can reach the server over plain HTTP; the owner deferred such a rule on 2026-10-24 (D-156). It would be the owner's own step on the Pi, outside ~/kvitt (D-125).
• The Memory limit column is advisory on the Kvitt Pi (D-156, owner 2026-10-24): compose.yaml keeps its mem_limit lines, but the Pi's kernel runs without the memory cgroup, so Docker warns at docker compose up and does not enforce the limits. The warning is accepted; the RSS budget is checked with docker stats (§10.10).
• One uid for both containers (D-105, revised by D-125): sqlite3 .backup on the WAL database must open the -shm file the server owns, so backup runs as the server's uid. On the Pi that uid is the owner's own, so every file in data/ and backups/ belongs to the owner, the two secret files are the owner's with mode 0600 (chmod 700 secrets && chmod 600 secrets/*), and a restore moves files with plain mv and cp (§10.9). The images need no particular uid: the server image's USER 10001 is only its default, which compose's user: overrides (the binary needs no account and nothing writable outside /data), and supercronic runs as any uid; the owner's uid has no account inside either image, so backup gets HOME=/tmp for rclone's cache. rclone writes refreshed access tokens back to its config, and the mounted file is read-only, so backup.sh works on a private copy in /tmp on every run (D-105).
• Each container mounts only its own secrets, read-only (D-117): the server never sees the Drive token, and the backup container never sees the FCM key or the Enable Banking keys (secrets/cards/, D-175). create_host_path: false makes a missing secret file stop docker compose up with "bind source path does not exist" instead of Docker creating a root-owned directory in its place. These two, and since D-175 the Enable Banking key files in secrets/cards/, are the only secret files on the Pi.
• The development stack (infra/dev/compose.yaml) is unchanged by D-125: both containers there run as uid 10001 (§10 intro).

.env keys (exhaustive, D-125, revises D-103; two optional keys added by D-175): exactly the nine keys compose.yaml reads, and nothing else reads .env on the Pi. The two card keys KVITT_EB_APP_ID (the Enable Banking application id, shared by both users or the owner's) and KVITT_EB_MEMBER_APP_ID (the partner's own application, empty when the shared one serves her, CP-13) may be empty; an application id is not a secret (its private key is, in secrets/cards/). KVITT_REGISTRY (gitea.lan/jacobh2); KVITT_TAG (the image tag of both services, v1.0.N; a deploy or a rollback changes it, §10.10); KVITT_PUBLIC_HOST (the Kvitt host name, owner-chosen, recorded in HANDOFF; kvitt.suorra.duckdns.org in the template); HA_HOST (NPM's LAN IPv4 address, an IP literal rather than an mDNS name such as homeassistant.local, which the container cannot resolve; the template's only CHANGE_ME); KVITT_UID and KVITT_GID (id -u and id -g of the owner on the Pi; 1000 in the template); RCLONE_FOLDER_ID (the Drive folder id of OQ-4, filled in the template). Compose refuses to start while one of the seven required keys is unset (${VAR:?…}; the two card keys default to empty); nothing else checks the values, since there is no install script. Removed keys: HA_PORT, HA_USER, HA_CERT_DIR (D-120); the informational KVITT_PI_HOST and KVITT_PI_SSH_USER, read by nothing on the Pi (2026-10-20, 200c99f, revises D-103; the owner's scp commands and NPM name <kvitt-pi-address> instead); RCLONE_REMOTE (fixed to gdrive: in compose.yaml); KVITT_REGISTRY_USER and KVITT_REGISTRY_TOKEN (D-125: private packages mean a one-time docker login gitea.lan on the Pi). On the Mac, infra/publish-apk.sh reads KVITT_PUBLIC_HOST from infra/pi/.env (§10.6).

10.3 Images, registry and build

• Image names (D-104, D-120): ${KVITT_REGISTRY}/kvitt-server, ${KVITT_REGISTRY}/kvitt-backup, with KVITT_REGISTRY=gitea.lan/jacobh2 (was ${KVITT_REGISTRY}/kvitt/<name>).
• The Gitea Actions workflow (D-104; the fallback since D-211, see the Mac build below): .gitea/workflows/build-images.yaml, following the owner's working example workflow. Runner label host: act_runner 0.6.1 on a Raspberry Pi 3 with 1 GB RAM, with an Alpine job container; the builds run on that Pi itself. sh steps, apk add git docker-cli docker-cli-buildx, docker login gitea.lan as ${{ github.actor }} with kvitt_cicd, a user-level secret of the repository owner jacobh2 (created by the owner; a user-level secret of the repository owner reaches the repository), a plain-HTTP buildx builder local-http-builder (buildkitd.toml with http = true for gitea.lan) created once and reused so its BuildKit cache survives, and actions/checkout@v4 (below). The token is interpolated into the login step's run line (printf '%s' "${{ secrets.kvitt_cicd }}" | docker login …), the owner's proven form, because the env-based form (env: REGISTRY_TOKEN: ${{ secrets.kvitt_cicd }}) came through empty on act_runner 0.6.1 ("password is empty" on the first run, 2026-10-19); act_runner masks the value in the log (4f69ae0, D-120 point 7; this reverses the L-8 fix of e70fe0d). kvitt_cicd needs only the write:package scope, because the git tag push goes through the credentials actions/checkout stored (the job's own token) (D-117); the tag push worked on the first successful run (its v1.0.0 tag is why the next run made v1.0.1). Checkout (3820f9c): a cone-mode sparse checkout (sparse-checkout server, web, contracts (both added by D-137) and infra/backup, sparse-checkout-cone-mode: true), what the two builds read (the server image builds from the repository root with the allowlist .dockerignore since D-137; the backup image from infra/backup), which makes the action fetch with --filter=blob:none, so only those paths' blobs are downloaded and the Android screenshot PNGs are not checked out; fetch-depth: 0 stays, because "Determine Version" needs every v1.0.* tag and with a shallow fetch fetch-tags brings only the tags that point at the fetched tip (the full fetch carries commits and trees, no blobs). The temporary "Diagnose secrets" step (dd07ca4) is removed (3820f9c). Every buildx push passes --provenance=false and --metadata-file, and a step "Print image digests" prints each pushed image's digest, which the owner compares with the digest the Pi pulled (docker image inspect, §10.10; the Pi keeps no digest record since D-125, which revises D-117 point 5). Triggers: a push touching server/**, web/**, contracts/** (the last two added by D-137), infra/backup/** or .gitea/workflows/**, and workflow_dispatch (infra/cert-sync/** dropped by D-120). Version v<MAJOR>.<MINOR>.<PATCH> with MAJOR 1 and MINOR 0 set in the workflow: the next patch after the newest v1.0.* git tag (v1.0.0 when there is none); each image is tagged with it and latest, and the git tag is pushed after the build. That tag is the Pi's KVITT_TAG (§10.2, §10.10); it says nothing about the APK version (§10.6). The Pi runner passes --build-arg CARGO_BUILD_JOBS=1 to the server build (Pi 3, 1 GB), and server/Dockerfile honours it (ARG CARGO_BUILD_JOBS in its build stage, passed to cargo as --jobs only when set; unset on the Mac means one job per core; b4d9467). "Determine Version" also sets VERSION_CODE to git rev-list --count HEAD (the full history is fetched, fetch-depth: 0), and the server build passes --build-arg KVITT_VERSION_CODE=$VERSION_CODE, the web client's version code (§15.3, v0.34). Runs on the owner's Pi runner: the first run (2026-10-19) failed at the login with the env-based form; the next ones failed at the login with an empty secret, because the user-level secret was misnamed on the owner's side (found with the diagnostic step, fixed by the owner on 2026-10-19). Run 69 succeeded: login, version v1.0.0, kvitt-backup built and pushed in 5 min 20 s, kvitt-server in 2 h 42 min (the first build on the Pi 3 with CARGO_BUILD_JOBS=1; later runs reuse the builder's cargo cache), the git tag pushed. The push of the sparse checkout (3820f9c) produced v1.0.1, the tag the Pi uses. Since 28fa71b (2026-10-20) the workflow's comments and infra/build-images.sh's closing hint give the compose deploy (cd ~/kvitt, set KVITT_TAG, docker compose pull && docker compose up -d) and docker image inspect instead of /opt/kvitt/deploy.sh and /opt/kvitt/deployed-digests; the workflow's header still says "NOT YET RUN" and that the first build's duration is unknown. Unverified risk: the workflow pushes a git tag, and whether that push re-triggers the path-filtered workflow is not known.
• Script infra/build-images.sh [tag] on the Mac, the normal path since D-211 (the fallback under D-104 and D-156): builds the two images for linux/arm64, tag defaults to the short git SHA of HEAD, also tags latest; pushes when infra/secrets/registry.env (git-ignored: KVITT_REGISTRY, optional KVITT_REGISTRY_USER and KVITT_REGISTRY_TOKEN) exists, otherwise builds locally and prints the exact push commands. Refuses to run with a dirty working tree or while a Gradle build holds the tools/gradle-serial.sh lock (the lock check shared through tools/gradle-lock.sh, 2fac1ec). Works with Docker buildx and with Podman.
• Where images are built (owner, 2026-10-24, D-211, revises D-156 point 5): on the owner's Mac with Podman, infra/build-images.sh v1.0.N; the Gitea workflow on the Pi 3 runner stays the fallback (about three hours per run and disk pressure on its 15 GB card; the owner cancels runs it queues). Tag rule: git fetch --tags, then the next v1.0.N after the highest v1.0.* tag on origin; the images carry that tag and latest, and the same tag is pushed as a git tag on the built commit (git tag v1.0.N && git push origin v1.0.N), so the workflow's own numbering continues after it (v1.0.3 = 8fa9198, the first Mac build). Registry from the Mac: gitea.lan on port 80, plain HTTP; infra/secrets/registry.env (git-ignored) holds KVITT_REGISTRY=gitea.lan/jacobh2, KVITT_REGISTRY_USER and a write:package token as KVITT_REGISTRY_TOKEN. The Pi's own .env keeps KVITT_REGISTRY=gitea.lan:3001/jacobh2, the port it reaches the same registry on locally; both name the same images. Podman marks the registry insecure in two places, ~/.config/containers/registries.conf.d/kvitt.conf on the Mac and /etc/containers/registries.conf.d/kvitt.conf inside the Podman machine, each [[registry]] location = "gitea.lan" insecure = true (owner's allowance 2026-10-24 for these files outside the repository). Two script fixes made the Mac path work: the server build gets --build-arg KVITT_VERSION_CODE=<git rev-list --count HEAD> as the workflow passes it (f15fa23), and the engine test captures docker version before matching it (8fa9198: under pipefail, grep -q closed the pipe early, docker version died of SIGPIPE and the script chose docker over Podman). The script prints no image digests, so the digest comparison of §10.10 applies to workflow builds. If the fallback runs, the owner still runs docker builder prune -af on the runner Pi between builds (its disk reached 11 of 15 GB); that can drop the BuildKit cache, so the next server build there may be a full one.
• Web client (D-132, as built D-137, 50a0d67): the server image's build context is the repository root (docker build -f server/Dockerfile .) with an allowlist .dockerignore at the root: everything is excluded except server, web and contracts, and inside them server/target, server/data, web/node_modules, web/dist, SQLite and .db files, APKs, .pem files, .env files and .DS_Store are excluded too, so the Android project, the docs, the goldens, worktrees and secrets never enter the context; server/.dockerignore is removed (infra/backup/Dockerfile builds from its own directory and does not read the root file). server/Dockerfile has three stages: (1) web: docker.io/library/node:24.22.1-bookworm-slim pinned by the digest of its multi-arch index (Node 24, the Active LTS line on 2026-10-21), on $BUILDPLATFORM (the output is static files, so an amd64 build never emulates npm), npm ci with a BuildKit npm cache, then npm run build in /repo/web beside /repo/contracts (the web build may read ../contracts), failing unless dist/index.html exists; the stage has no .git, so ARG KVITT_VERSION_CODE=1 is passed to npm run build as the environment variable KVITT_VERSION_CODE, the web's version code (§15.3; default 1, the workflow passes the commit count, v0.34); a web/ without package.json and package-lock.json fails the build by design; (2) the Rust build stage, which copies the web stage's dist to /out/web, so it orders the two builds and npm and rustc never run at once on the 1 GB Pi 3 runner (BuildKit would otherwise run the independent stages in parallel; a web-only change re-runs the cargo step, which finds nothing to compile); CARGO_BUILD_JOBS=1 stays; (3) the runtime stage, which copies /out/web to /app (owned by root, read-only for uid 10001; KVITT_WEB_DIR §10.4, serving §15.4). The workflow builds with context . and file: server/Dockerfile, its sparse checkout and path triggers add web and contracts (above); infra/build-images.sh builds kvitt-server with context .; infra/dev/compose.yaml has no build section, so infra/dev/build.sh builds with the repository root as context (KVITT_SERVER_BUILD_CONTEXT still overrides it). The Pi runner builds the Node stage too (its duration on the Pi 3 not yet measured); the web client adds no image and no service.
• server image: multi-stage (since D-137 the Node web stage above runs first; the stages below are the Rust build and the runtime). Stage 1 rust:<version>-bookworm, where <version> is the exact Rust release pinned in server/rust-toolchain.toml (the current stable when M2a pins it; the two always change together), builds kvitt-server and kvitt-import in release mode with --locked for aarch64-unknown-linux-gnu (native on the M4; no target-cpu=native, the Pi 3 is a Cortex-A53). Stage 2 gcr.io/distroless/cc-debian12:nonroot (arm64) pinned by digest, with the two binaries in /usr/local/bin/, user 10001, entrypoint kvitt-server, command serve. The Dockerfile selects the Rust target from TARGETARCH: arm64 (aarch64-unknown-linux-gnu) is the shipped target; amd64 (x86_64-unknown-linux-gnu) also builds, emulated on the Mac, for local use only. Since M4 the server depends on reqwest with rustls on aws-lc-rs and on jsonwebtoken (§6.3): aws-lc-rs compiles C code, so the arm64 build stage needs a C toolchain beside Rust, and the distroless runtime image must carry CA roots for the platform verifier to reach Google's endpoints. The dev image (infra/dev, linux/arm64 on the Mac) was rebuilt with these crates on 2026-10-18 and built cleanly. The Pi image's C stage and CA roots, and an OAuth plus FCM call from the image, were confirmed on the Mac on 2026-10-18 (docs/spikes/pi-image-arm64.md, landed 3e6c337): arm64 image 63.8 MB, cold build 48 s, CA bundle from distroless, binaries run natively; running on the Pi itself is M2c-pi's.
• backup image: alpine with sqlite, gzip, tar, rclone and tzdata, and infra/backup/backup.sh run by supercronic; the healthcheck is infra/backup/healthcheck.sh.
• The backup sidecar schedules with supercronic instead of busybox crond (D-104): it runs as a non-root user, and busybox crond started as a non-root user runs no job (tested 2026-10-18 in alpine 3.24.2). The schedule is unchanged (30 3 * * *).
• Pinned versions (resolved 2026-10-18, D-104; table in infra/README.md "Versions"): Alpine alpine:3.24.2@sha256:294b683cb724975bec92580e1e685676bd4b50bda910ddb8c51d4cabeaec77e6 for the backup sidecar; backup packages supercronic 0.2.49 beside M2c-dev's sqlite, rclone and tar. The Caddy pin and the cert-sync packages left with D-120; Nginx Proxy Manager is the owner's existing install, and the block of §10.5.2 was written against NPM v2.16.0's templates. Docker Engine on the Kvitt Pi (a prerequisite, already installed, D-125) comes from Docker's Debian arm64 apt repository (docs.docker.com: the Raspberry Pi OS page is for 32-bit only), docker-ce 5:29.8.2 with docker-ce-cli, containerd.io, docker-buildx-plugin and docker-compose-plugin.
• No scripts on the Pi (D-125, revises D-103): install.sh, deploy.sh, bootstrap.sh, backup-now.sh, install-apk.sh and lib.sh were removed in 6e5981d. Their equivalents are plain docker compose commands the owner runs in ~/kvitt: install = copy compose.yaml, .env and secrets/ from the Mac, mkdir -p data/apk backups import, docker compose pull && docker compose up -d, curl localhost:8080/health; bootstrap = docker compose exec server kvitt-server bootstrap; partner invite = docker compose exec server kvitt-server invite-partner; one backup = docker compose exec backup /backup.sh; deploy and rollback §10.10; APK §10.6; restore §10.9. A changed compose.yaml or .env is copied again the same way. The checks install.sh made on .env are gone (compose refuses an unset key, §10.2); its /opt/kvitt/deployed-digests record is replaced by docker image inspect (§10.10).
• The Pi's Docker daemon must trust gitea.lan as an insecure (plain HTTP) registry (insecure-registries in /etc/docker/daemon.json). This is a prerequisite the owner keeps (the Kvitt Pi already has it for another project); nothing of Kvitt edits the daemon or the system (D-125; install.sh added it with sudo, D-103). Were the packages private, the owner runs docker login gitea.lan once with a read:package token (D-125).

10.4 Server configuration and CLI

Environment variables (exhaustive):

Variable	Default	Meaning
KVITT_DATA_DIR	/data	Holds kvitt.sqlite, pictures/, apk/
KVITT_BIND	0.0.0.0:8080	Listen address
KVITT_PUBLIC_URL	none: required (D-123)	Used in invite links and the landing page. Unset or empty, every kvitt-server command exits 1 with a configuration error (configuration: KVITT_PUBLIC_URL is not set … on stderr) before opening the database; there is no built-in host (the fallback DEFAULT_PUBLIC_URL was removed by D-123). The Pi's compose sets https://${KVITT_PUBLIC_HOST} (port 443, D-124) from the Kvitt host name (KVITT_PUBLIC_HOST, owner-chosen, recorded in HANDOFF) (D-120); the development stack sets http://<Mac LAN address>:<port> (infra/dev/up.sh; the dev compose falls back to http://localhost:8080)
KVITT_FCM_CREDENTIALS	/secrets/fcm-service-account.json	Service-account key; if the file is missing, push is disabled and a warning is logged at start
KVITT_FCM_PROJECT_ID	kvitt-1337	FCM project
KVITT_TRUSTED_PROXY	none	IP literal or host name whose resolved address may set X-Forwarded-For (not a CIDR). The default none (NO_TRUSTED_PROXY in config.rs, compared ignoring case and surrounding white space) means no proxy and is never looked up (D-123; was caddy); an empty value counts as unset. Compose sets it to HA_HOST, NPM's LAN IPv4 address (D-120). The server must start when the name does not resolve (as on the development stack, which has no proxy, D-022 unchanged); with none or an unresolvable name no peer is trusted and the peer address is the client IP (D-022). The name is re-resolved at most every 60 seconds (D-032)
KVITT_WEB_DIR	/app	Directory of the built web client, served under /app/ (D-135, §15.4). Missing (an image without the web client, cargo run in development): every /app path is 404 not_found
KVITT_EB_APP_ID	empty	Enable Banking application id for card purchases (D-175, CP-13): the admin's, and the member's too unless KVITT_EB_MEMBER_APP_ID is set. Empty, or its key file missing or unreadable: card features are disabled for that user (E-36 available false), with one warning at start, as push is (§14.6)
KVITT_EB_KEY_FILE	/secrets/cards/enable-banking.pem	The PEM private key of KVITT_EB_APP_ID, as Enable Banking's control panel downloads it (<application id>.pem, renamed)
KVITT_EB_MEMBER_APP_ID	empty	The member's own Enable Banking application (CP-13 fallback); empty: the member uses KVITT_EB_APP_ID
KVITT_EB_MEMBER_KEY_FILE	/secrets/cards/enable-banking-member.pem	The PEM private key of KVITT_EB_MEMBER_APP_ID
KVITT_EB_API_URL	https://api.enablebanking.com	Enable Banking API base URL; tests point it at a local stub
RUST_LOG	info	tracing filter

The time zone Europe/Stockholm is a constant in code, not configuration.

Files under KVITT_DATA_DIR:

• kvitt.sqlite (+ -wal, -shm)
• pictures/<user_id>/<picture_version>-512.jpg and -128.jpg; older versions are deleted after a successful upload. E-10 deletes the JPEGs and leaves an empty marker file <picture_version>-removed in pictures/<user_id>/; the next upload uses the highest version on disk (JPEG or marker) plus one, so a cache keyed by (user_id, picture_version) never shows a removed picture. The first upload is version 1 (D-030).
• apk/latest.json and apk/kvitt-<version_code>.apk

kvitt-server subcommands (exhaustive):

Command	Effect	Exit codes
serve	Run migrations, start scheduler, push sender and HTTP server	0 on clean shutdown (SIGTERM drains in-flight requests up to 10 s)
bootstrap	FR-1	0 ok, 2 already initialized
pair-device --user <user_id>	AC-1.6	0 ok, 3 unknown user
invite-partner	Creates a partner invite by the admin, as E-12 (D-113)	0 ok, 2 household full, 3 no admin
rotate-epoch	Sets a new random sync_epoch and prints it on stdout (§10.9)	0 ok, 1 database error
healthcheck	Calls http://127.0.0.1:<port of KVITT_BIND>/health (8080 by default), exit 0 if 200; used by the compose healthchecks of both stacks (no curl in the image)	0 or 1
migrate	Run migrations only	0

Run them on the Pi in ~/kvitt with docker compose exec server kvitt-server <command> (or docker compose run --rm server <command> when server is stopped) (D-125). Outside Docker, from the workspace root server/: cargo run -p kvitt-server -- <command> (the -p is needed because the workspace has two binaries), with KVITT_DATA_DIR set (server/README.md).

10.5 TLS

TLS terminates in the owner's Nginx Proxy Manager (NPM) on the Home Assistant Pi (D-120; Caddy and cert-sync, which held this section until v0.20, are removed). Kvitt has its own public host name, KVITT_PUBLIC_HOST (owner-chosen, recorded in docs/HANDOFF.md), because icehack.asuscomm.com is NPM's proxy host for Home Assistant and NPM selects the proxy host by name, not by port. KVITT_PUBLIC_URL is https://${KVITT_PUBLIC_HOST}, with no explicit port: Kvitt is served on the default HTTPS port 443, on which NPM listens for every proxy host and selects by name (D-124). Serving Kvitt under a path prefix of another name (for example icehack.asuscomm.com/kvitt/) is not supported. The router forwards external TCP 443 to the Home Assistant Pi's 443 (NPM), already in place for Home Assistant, which serves Kvitt too: no new router rule (D-124; the 8443 rule of D-120 is not used); nothing is forwarded to the Kvitt Pi. NPM issues and renews the name's Let's Encrypt certificate through the HTTP-01 challenge on port 80, which already reaches NPM. The owner sets up the proxy host in NPM's web UI from infra/README.md "Pi: what the owner does", step 4 (step 6 before D-125); no agent and no script touches NPM. The proxy host carries the app gate of §8.5 (D-126) in its Custom Nginx Configuration (§10.5.2), set up by step 4a once both phones run an APK that carries the key; an APK without the key cannot reach the server from outside the LAN, its update download included. Since D-130 the gate also lets the web client through (§8.5, §15.2): its files under /app/, the invite accept and bearer-token requests.

10.5.1 Nginx Proxy Manager

NPM's web UI (Home Assistant, Settings, Add-ons, Nginx Proxy Manager, Open Web UI), Hosts, Proxy Hosts, Add Proxy Host:

Tab	Field	Value
Details	Domain Names	<KVITT_PUBLIC_HOST> (currently kvitt.suorra.duckdns.org, HANDOFF)
Details	Scheme	http
Details	Forward Hostname / IP	<kvitt-pi-address> (the Kvitt Pi's LAN IPv4 address)
Details	Forward Port	8080
Details	Cache Assets	off
Details	Block Common Exploits	on
Details	Websockets Support	off
Details	Access List	Publicly Accessible (the app gate is in the Advanced block, D-126: an NPM access list checks addresses or HTTP basic auth, not a header, and basic auth would take the Authorization header the bearer token needs)
Custom Locations	(none)	left empty
SSL	SSL Certificate	Request a new Certificate: Let's Encrypt, HTTP challenge (Use DNS Challenge off), the owner's email address, Terms of Service accepted where shown
SSL	Force SSL	on
SSL	HTTP/2 Support	on
SSL	HSTS Enabled	on
SSL	HSTS Sub-domains	off
SSL	Trust Upstream Forwarded Proto Headers	off
Advanced	Custom Nginx Configuration	the block of §10.5.2, exactly, comments included

• Plain HTTP on the LAN: NPM forwards plain HTTP over the home LAN to <kvitt-pi-address>:8080, accepted by the owner (D-120). Anyone on the home LAN can also reach that port directly; such requests count against their own address for the limits of §8.6, and only HA_HOST may set X-Forwarded-For (§8.9).
• Client IP: NPM's request to the server carries X-Forwarded-For: <what the client sent>, <client address>. The server takes the last entry only when the TCP peer is KVITT_TRUSTED_PROXY, which compose sets to HA_HOST, NPM's LAN IPv4 address (an IP literal in .env, because the container cannot resolve an mDNS name such as homeassistant.local; nothing checks it since D-125); the server is unchanged (D-032, D-115, D-119). The router's forward keeps the internet client's source address, and Docker's published port keeps NPM's (DNAT, no SNAT, for traffic arriving on the LAN interface), so the per-IP limits see real addresses (checked once, §10.10). The server does not use X-Forwarded-Proto or Host: links are built from KVITT_PUBLIC_URL (E-12).
• X-Real-IP (accepted): NPM's nginx.conf takes the client address from X-Real-IP when the connection comes from 10/8, 172.16/12 or 192.168/16 (and the CDN ranges it downloads), so a device on the home LAN can choose its own client address for the rate limits. Internet clients arrive with their public address (the router's forward keeps the source address), so their X-Real-IP is ignored.
• HSTS: NPM sends Strict-Transport-Security with max-age=63072000; preload (two years, NPM's value) at server level. A browser then uses only HTTPS for <KVITT_PUBLIC_HOST>, on every port, and refuses certificate warnings for it; turning HSTS off later does not clear browsers that already stored it. Because the name is Kvitt's own nothing else is affected, but anything ever served under <KVITT_PUBLIC_HOST> (any port) must be HTTPS with a valid certificate too. The app does not rely on HSTS (release builds allow no cleartext, §8.5); it protects the landing page in a browser.
• Health checks (D-125, revises D-120 point 6; no script runs them): after a start or a deploy the owner runs curl -s localhost:8080/health on the Kvitt Pi, and checks /health through NPM from the Pi (curl -fsS --resolve <KVITT_PUBLIC_HOST>:443:<HA_HOST> https://<KVITT_PUBLIC_HOST>/health, with the certificate checked; the Kvitt Pi is on the LAN, so no key is needed, D-126) and from outside: with the app gate in place (D-126) a browser outside the LAN gets a closed connection by design, so the outside check is the app's About screen (S-22) on the phone with Wi-Fi off, or curl -fsS -H "X-Kvitt-App: $KEY" https://<KVITT_PUBLIC_HOST>/health from outside the home network (before the gate: https://<KVITT_PUBLIC_HOST>/health in Chrome on the phone with Wi-Fi off); infra/README.md "Pi: what the owner does" steps 3, 4, 4a and 6.

10.5.2 Custom Nginx Configuration

The block pasted into the proxy host's Advanced tab (D-120; it carries over D-117's response headers and log redaction). Written against NPM v2.16.0's proxy host template (backend/templates/proxy_host.conf); as of v0.28 it reads (infra/README.md, step 4, and the file infra/npm/kvitt.conf, three identical copies; the app gate lines added by D-126, the web client's gate lines and the $kvitt_csp variable by D-130 and D-132, the rest as of 62f5279):

# Kvitt (SPEC §10.5.2, D-120, D-126, D-130). NPM, Proxy Host <KVITT_PUBLIC_HOST>, Advanced tab, Custom Nginx Configuration.
# App gate (SPEC §8.5, D-126): outside the home LAN only a request carrying the key built into the app passes;
# everything else gets the connection closed (444: nothing sent, nothing to fingerprint). Put the key from
# android/local.properties (kvitt.appKey) in place of KVITT_APP_KEY. To rotate, add a second if-line with the new key.
# The LAN check reads $realip_remote_addr, the address that really connected: NPM replaces $remote_addr with the
# request's own X-Real-IP header for private peers, so $remote_addr could be forged. Let's Encrypt's renewal passes.
set $kvitt_gate 0;
if ($http_x_kvitt_app = "KVITT_APP_KEY") { set $kvitt_gate 1; }
if ($realip_remote_addr ~ "^192\.168\.1\.") { set $kvitt_gate 1; }
if ($uri ~ "^/\.well-known/acme-challenge/") { set $kvitt_gate 1; }
# Web client (SPEC §15, D-130): its files under /app/, the invite accept it logs in with, and any request carrying a
# bearer token (the server checks the token; unknown tokens are rate-limited per IP), except /health, /setup/, /i/
# and /apk/, which stay LAN-or-key only.
if ($uri ~ "^/app(/|$)") { set $kvitt_gate 1; }
if ($uri = "/invites/accept") { set $kvitt_gate 1; }
# Card connection (SPEC §9.12, D-163): the bank redirects the user's browser here, without the app key.
if ($uri = "/cards/callback") { set $kvitt_gate 1; }
set $kvitt_bearer 0;
if ($http_authorization ~ "^Bearer ") { set $kvitt_bearer 1; }
if ($uri ~ "^/(health|setup/|i/|apk/)") { set $kvitt_bearer 0; }
if ($kvitt_bearer = 1) { set $kvitt_gate 1; }
if ($kvitt_gate = 0) { return 444; }
# Server body: 1 MiB, PUT /me/picture 5 MiB (SPEC §8.6); the server answers anything larger with its own 413.
client_max_body_size 6m;
# No long-poll in the API (SPEC §14.3); 60 s between two reads from the server.
proxy_read_timeout 60s;
# Response headers (D-117). They live at server level, so no location below may use add_header (nginx would then
# drop all of these in it); NPM's HSTS line (SSL tab) sits at the same level. The server's own copy is hidden, so
# each header appears once (the landing page sends Referrer-Policy itself).
proxy_hide_header Content-Security-Policy;
proxy_hide_header X-Content-Type-Options;
proxy_hide_header X-Frame-Options;
proxy_hide_header Referrer-Policy;
# The web client under /app/ (D-132) needs its own scripts, styles, images and API calls: one variable, still one
# server-level add_header.
set $kvitt_csp "default-src 'none'; style-src 'unsafe-inline'; base-uri 'none'; form-action 'none'; frame-ancestors 'none'";
if ($uri ~ "^/app(/|$)") { set $kvitt_csp "default-src 'none'; script-src 'self'; style-src 'self' 'unsafe-inline'; img-src 'self' blob: data:; font-src 'self'; connect-src 'self'; base-uri 'none'; form-action 'none'; frame-ancestors 'none'"; }
add_header Content-Security-Policy $kvitt_csp always;
add_header X-Content-Type-Options nosniff always;
add_header X-Frame-Options DENY always;
add_header Referrer-Policy no-referrer always;
# Replaces NPM's own "location /" (NPM leaves it out when this field has one), whose add_header X-Served-By would
# drop the headers above. $forward_scheme, $server and $port are NPM's Details tab values.
location / {
  proxy_set_header Host $host;
  proxy_set_header X-Forwarded-Proto $scheme;
  proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
  proxy_set_header X-Real-IP $remote_addr;
  proxy_pass $forward_scheme://$server:$port$request_uri;
}
# Invite links /i/<code>?from=<name>: neither the code nor the inviter's name may reach a log (SPEC §8.7). NPM's
# access log format writes the whole $request_uri, query string included, so this path is not logged at all, and
# its error log (which would carry the request line on a 502) goes nowhere.
location ^~ /i/ {
  access_log off;
  error_log /dev/null crit;
  proxy_set_header Host $host;
  proxy_set_header X-Forwarded-Proto $scheme;
  proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
  proxy_set_header X-Real-IP $remote_addr;
  proxy_pass $forward_scheme://$server:$port$request_uri;
}
# Card connection callback /cards/callback?code=…&state=… (SPEC §9.12, D-163): the query carries a one-time
# authorisation code and the attempt's state, so this path is not logged at all, a 502 included.
location = /cards/callback {
  access_log off;
  error_log /dev/null crit;
  proxy_set_header Host $host;
  proxy_set_header X-Forwarded-Proto $scheme;
  proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
  proxy_set_header X-Real-IP $remote_addr;
  proxy_pass $forward_scheme://$server:$port$request_uri;
}

• Card callback (D-163, v0.35): /cards/callback passes the gate from outside (the bank's redirect reaches it from the user's browser, a Custom Tab on mobile data included, which carries no app key) and is not logged by NPM (location = /cards/callback, as /i/), because its query holds the authorisation code and state. The exemption tests the normalised $uri exactly, so no other path rides on it. The server answers it with its own page (E-39) and the D-117 headers apply (the page needs no script; its one link is an <a href>). Before the gate goes in, the line is left out with the other gate lines. K1 updates infra/npm/kvitt.conf and infra/README.md step 4 and repeats the nginx check (nginx -t, a request to /cards/callback from a non-LAN address reaching the upstream, no access-log line).
• Response headers (D-117): Content-Security-Policy, X-Content-Type-Options, X-Frame-Options and Referrer-Policy are set at server level with always, and the server's own copies are hidden with proxy_hide_header, so each header appears once (the landing page sends Referrer-Policy: no-referrer itself, AC-2.5). NPM's HSTS line from the SSL tab sits at the same level.
• Its own location /: nginx drops every add_header inherited from the server level in a location that has an add_header of its own, and NPM's default location / has one (X-Served-By), which would silently drop the four headers. NPM leaves its default location out when the Custom Nginx Configuration contains location / (NPM matches it with the regex ^(?:.*;)?\s*?location\s*?\/\s*?{), so the block brings its own, without add_header. Its proxy_pass uses NPM's Details values ($forward_scheme, $server, $port). If a later NPM release changes the proxy host template, the headers are checked again (§10.10).
• client_max_body_size 6m: above the server's own limits (1 MiB, 5 MiB for PUT /me/picture, §8.6), which answer payload_too_large themselves; larger bodies get NPM's 413. proxy_read_timeout 60s: the API has no long-poll.
• Logs (§8.7): NPM writes one access log line per request to /data/logs/proxy-host-<id>_access.log inside NPM, in its proxy format: time, cache and upstream status, status, method, scheme, host, "$request_uri" (the path with its query string), [Client <address>], length, gzip ratio, [Sent-to <KVITT_PI_HOST>], user agent and referer. It logs no request headers, so the Authorization token is never logged. Query strings are logged for every path except /i/; the API's other query parameters are since and limit (GET /sync) and size and v (pictures), which hold no personal content. location ^~ /i/ turns the access log off and sends its error log to /dev/null, so neither the invite code nor the inviter's name (?from=) reaches a log, a 502 included. Errors on other paths (for example a 502 while the server is down) go to proxy-host-<id>_error.log with the request line.
• App gate (§8.5, D-126): set, if and return are rewrite-module directives; at server level they run in NPM's server rewrite phase, before a location is chosen, so the gate covers every location, /i/ included, and no add_header is involved. KVITT_APP_KEY is replaced by the key from android/local.properties; a rotation adds a second if ($http_x_kvitt_app = …) line. $realip_remote_addr is the TCP peer: NPM's nginx.conf has set_real_ip_from 10/8, 172.16/12 and 192.168/16 with real_ip_header X-Real-IP, which would let a LAN client, or every client if NPM saw a Docker bridge address (security review I-5), choose $remote_addr. The Let's Encrypt exemption tests the normalised $uri, which location matching uses, so /.well-known/acme-challenge/../../health is closed; that path is served by NPM's own location ^~ /.well-known/acme-challenge/ from its webroot, never proxied. NPM's own server-level rules come first in its template: Force SSL answers port 80 with a 301 to https:// (Let's Encrypt follows it, which is why the exemption is needed on 443), and Block Common Exploits answers its patterns with 403. If NPM saw a Docker bridge address for every client, the LAN check would match nothing; if the router rewrote internet clients to its LAN address, everything; NAT hairpin makes a LAN client appear as the router's 192.168.1.1, still inside the /24. The owner's acceptance test (infra/README.md step 4a): on the home Wi-Fi https://<KVITT_PUBLIC_HOST>/i/TEST shows the page in a browser, with Wi-Fi off it gives a connection error, and the app's About screen still shows the server version.
• Web client gate (D-130): /app and /app/… and POST /invites/accept pass on the normalised $uri (so /app/../health is closed); a bearer header passes through the helper variable $kvitt_bearer, which the next line clears for /health, /setup/, /i/ and /apk/, because nginx's if takes one condition. The value of the bearer header is not checked by NPM (the server does). Before the gate first goes in (step 4a), the gate lines from set $kvitt_gate 0; to return 444; are left out together.
• Content-Security-Policy (D-132): $kvitt_csp holds the D-117 policy, and for /app/ the web client's: its own origin for scripts, styles (inline styles allowed, as D-117 allows them), images (plus blob: for profile pictures fetched with the token and data:), fonts and API calls; default-src 'none', base-uri 'none', form-action 'none', frame-ancestors 'none' as before. One server-level add_header with a variable keeps the rule that no location has an add_header. The server's own /app/ header (W7) is hidden like the others and should carry the same policy (it is the one the development stack shows).
• Verified on the Mac on 2026-10-21 (D-130, D-132): nginx -t (nginx:alpine 1.31.7) of the block above with a test key in a server block whose upstream is a stub, and 17 requests from a non-LAN address: /health, /sync without a header, /sync with Authorization: Basic, /invites/acceptx, /application, /app/../health and, with a bearer header, /health, /i/TEST, /apk/latest and /setup/status were closed with no reply; /health with the key, /app, /app/, /app/login, POST /invites/accept, /accounts with a bearer header and the ACME path reached the upstream; /app/ carried the web policy and /accounts the D-117 policy, each once, with the other three headers. Not checked: NPM's own template and real_ip settings with these lines (the 2026-10-21 D-126 rehearsal covered them for the earlier lines), the real proxy host.
• Verified on the Mac on 2026-10-21 (D-126): the block above, with a test key, inside a server block with NPM v2.16.0's letsencrypt-acme-challenge.conf and block-exploits.conf includes and its real_ip settings, run by the openresty 1.31.1.1 of the jc21/nginx-proxy-manager:2 image (v2.16.0): nginx -t successful; without the header, with a wrong key, with a forged X-Real-IP: 192.168.1.50, on /i/ and /apk/files/ without the header, and on /.well-known/acme-challenge/../../health, the connection was closed with no reply; with the key /health and /i/ reached the upstream with the D-117 headers; an ACME token file was served; a second key line passed; a peer matching the LAN pattern passed without the header; with $remote_addr instead of $realip_remote_addr the forged X-Real-IP passed (why the block uses the latter). Not checked: HTTPS and HTTP/2 through NPM's real proxy host, the router and the real LAN addresses (the owner's acceptance test).
• Verified on the Mac on 2026-10-19 (D-120): nginx -t (nginx:alpine 1.31.7) of the block inside a minimal server block and inside a copy of NPM v2.16.0's nginx.conf with the proxy host rendered as NPM's template renders it for the §10.5.1 settings, both successful; a Podman rehearsal of the server image built from server/Dockerfile (arm64, hardened as on the Pi) behind that nginx with a self-signed certificate, 21 checks passed: the four headers and Strict-Transport-Security once each over HTTP/2 and no X-Served-By; one Referrer-Policy on the landing page; http:// answered 301 to https://; a 7 MB body refused by nginx (413), a 2 MB body answered by the server (payload_too_large); the rate limit applied per forwarded client and a forged X-Forwarded-For did not escape it; the invite code, the name and /i/ absent from nginx's access and error logs after /i/, //i/ and /%69/ requests and a 502 on /i/. Not checked (needs the real hosts): NPM's own UI and Let's Encrypt for the Kvitt host name, the router forward.

10.5.3 Fallback: NPM down

• NPM or the Home Assistant Pi down means Kvitt is unreachable from outside, and also from home over https://<KVITT_PUBLIC_HOST> (that path goes through NPM too). The server on the Kvitt Pi keeps running and nothing there needs to change; the phones keep working on their full local copy and sync when NPM is back (FR-15).
• On the home Wi-Fi only debug builds can reach the server directly, at http://<kvitt-pi-address>:8080 (AC-2.8 allows http:// to private LAN addresses in debug builds only). Release builds require HTTPS with a publicly trusted certificate (§8.5): there is no LAN fallback for the release app. A debug build is a separate app (se.hagstedt.kvitt.debug) with its own pairing and data, not a stand-in for the release app.
• If NPM cannot renew the Let's Encrypt certificate, it is fixed in NPM (SSL Certificates, the certificate, Renew Now; port 80 must reach NPM).
• The pinned-root switch of D-082 (kvitt.tls.pinnedRoot=true in android/gradle.properties; the pinned-root config is generated at build time from the template android/app/src/releasePinnedRoot/network_security_config.xml with the domain kvitt.publicHost, into the release resources only when kvitt.tls.pinnedRoot=true, a domain-config trusting only @raw/kvitt_root_ca; the build stops with a message while android/app/src/release/res/raw/kvitt_root_ca.crt is not committed, D-121, 038c603) remains available for a self-made root whose certificate would be uploaded to NPM as a Custom certificate. It is not prepared: no such root exists and none is committed.

10.6 APK hosting and release

• version_code = git rev-list --count HEAD on the commit being released; version_name = YYYY.MM.DD-<short sha> of that commit (its commit date in Europe/Stockholm). Both are passed to Gradle as properties kvitt.versionCode and kvitt.versionName by the release script; debug builds use 1 and dev.

• The release keystore is created once on the Mac (by the owner, or by an agent the owner allows; §11, D-024, D-101) at the root of the main checkout as kvitt-release.jks, with exactly:

  keytool -genkeypair -v -keystore kvitt-release.jks -alias kvitt -keyalg RSA -keysize 4096 -validity 10000
  

  The file is git-ignored by the *.jks pattern and never committed (D-101, revises D-024's "outside the repository"). android/local.properties holds its absolute path and secrets in the keys kvitt.release.storeFile, kvitt.release.storePassword, kvitt.release.keyAlias (kvitt), kvitt.release.keyPassword. Losing it means the phones must uninstall and reinstall (data comes back by sync). The owner keeps a copy of the file and its password in their password manager. Without these keys in local.properties, :app:assembleRelease builds an unsigned APK (M8). Release signing was verified on 2026-10-18: alias kvitt, RSA 4096, APK signature scheme v2.

• Release builds are R8-shrunk, optimised and obfuscated (isMinifyEnabled, isShrinkResources, proguard-android-optimize.txt plus android/app/proguard-rules.pro, no project keep rules needed as of 2026-10-18; landed c30a49e); the signed APK is about 10 MB (10.0 MB at a0259ab; 43 MB before R8); infra/publish-apk.sh saves mapping.txt next to the APK as kvitt-<version_code>.mapping.txt for retrace; mappings are never served and stay on the Mac, outside the Pi's data/ (D-103, D-125).

• infra/publish-apk.sh on the Mac (D-103): refuses a dirty working tree, reads KVITT_PUBLIC_HOST from infra/pi/.env (read, not sourced; it refuses a missing file or key, a CHANGE_ME value, anything that is not a host name, a URL included, and the old name icehack.asuscomm.com; landed 4b1ae0c, D-122), builds :app:assembleRelease through tools/gradle-serial.sh with -Pkvitt.versionCode, -Pkvitt.versionName and -Pkvitt.publicHost=<KVITT_PUBLIC_HOST>, prints the release server https://<KVITT_PUBLIC_HOST> (D-124) in its header and summary, refuses an unsigned APK, computes SHA-256 and size, and writes into infra/pi/out/apk/ (git-ignored) kvitt-<version_code>.apk, kvitt-<version_code>.mapping.txt and latest.json (written to a temp file, then renamed), keeping the newest 5 APKs with their mappings there. The owner then copies, from the Mac, the APK first and latest.json last straight into the server's data/apk/ on the Pi (scp infra/pi/out/apk/kvitt-<version_code>.apk jacobhagstedt@<kvitt-pi-address>:kvitt/data/apk/, then the same for infra/pi/out/apk/latest.json), so the server, which reads latest.json on every request, never announces a file it does not have; curl -s http://<kvitt-pi-address>:8080/apk/latest then shows the new version_code (D-125; install-apk.sh, with its SHA-256 check against latest.json and its copy into the named volume, is removed). The mapping files stay on the Mac. latest.json:

{
  "version_code": 412,
  "version_name": "2026.11.02-1a2b3c4",
  "file_name": "kvitt-412.apk",
  "size_bytes": 18234567,
  "sha256": "9f2c…64 hex chars…",
  "released_at": "2026-11-02T19:40:00.000Z"
}

• The release server's host name is a build property (D-121): kvitt.publicHost is read from the Gradle property (-Pkvitt.publicHost=…), else the key kvitt.publicHost in android/local.properties (the owner's, git-ignored), else the placeholder kvitt.example.invalid (RFC 2606; it never resolves, so a release built without the property cannot reach a real host). The build refuses a value that is not a host name. :app exposes it as BuildConfig.PUBLIC_HOST, as the manifest placeholder publicHost (the AC-2.6 https intent filter, no port, so it matches every port of the host, path prefix /i/, android:autoVerify="false", D-124) and as RELEASE_SERVER_URL = releaseServerUrl(host) = https://<host> (link/ReleaseServer.kt, releaseServerUrl in :feature:onboarding's ServerAddress.kt; RELEASE_SERVER_PORT removed, D-124); :feature:onboarding receives that URL through the Hilt qualifier @ReleaseServerUrl (§13.3 S-1), and :data through AppBuildInfo.releaseServerUrl, which S-22 shows before pairing (D-122). Invite-link parsing still accepts a server named by the link and drops an explicit default port (:443, :80) (AC-2.6, D-124). Tests and goldens use fixed fixture hosts. infra/publish-apk.sh passes -Pkvitt.publicHost from KVITT_PUBLIC_HOST in infra/pi/.env (above, §10.5, D-122); the owner may instead set the key in android/local.properties. Its sibling kvitt.appKey (D-126, next item) is read the same way.
• The app key is a build property too (D-126, modelled on D-121): kvitt.appKey from the Gradle property (-Pkvitt.appKey=…), else the key kvitt.appKey in android/local.properties, else empty (no X-Kvitt-App header sent); BuildConfig.APP_KEY (§8.5). A release APK carries the key it was built with, so the APK must be rebuilt after the key is set or rotated; infra/publish-apk.sh needs no change, because it builds on the Mac, where android/local.properties holds the key. An APK without the key cannot reach the server from outside the home LAN once the app gate is in NPM, its update download included, so both phones run a keyed APK before the gate goes in (infra/README.md step 4a). Anyone holding the APK holds the key; the owner alone distributes it (first install on both phones by hand) and rotates the key if an APK leaks (§8.5).
• With --deploy (D-139) the script copies the APK first and latest.json last itself, with the forced-command deploy key infra/secrets/pi_deploy_ed25519 (scp into data/apk/ only), and fails unless https://<KVITT_PUBLIC_HOST>/apk/latest, requested with X-Kvitt-App, returns the new version_code; the manual scp stays the fallback (infra/README.md "Publishing an APK").
• The server reads latest.json on each GET /apk/latest (no cache) and serves GET /apk/files/{file_name} only for a file_name matching ^kvitt-[0-9]+\.apk$ that exists, with Content-Type: application/vnd.android.package-archive.
• Downloads are limited to 10 per minute per client IP (§8.6, D-119); E-5 stays on the 60 per minute of the other unauthenticated endpoints. If one address still fetches /apk/files/ over and over (NPM's access log), the owner's stop-gap is to disable Kvitt's proxy host in NPM (Hosts, Proxy Hosts, the row's menu, Disable) until it stops; the router's 443 forward stays, because it also serves Home Assistant (D-124, infra/README.md). Since the app gate (D-126) a request from outside without the app key never reaches the server, so this concerns the home LAN or a leaked key.
• Older APKs stay in data/apk/ on the Pi until the owner removes them by hand (D-125; install-apk.sh kept the newest 5, D-103); infra/pi/out/apk/ on the Mac keeps the newest 5.
• The web client (D-132) is part of the server image: it is published by deploying a server image (§10.10), with no step of its own here; a browser loads the new version on its next page load (index.html is never cached, §15.4).

10.7 Firebase setup (M2c-dev, with a HUMAN sign-in)

No new command-line tool is installed for this (D-022): gcloud exists on the Mac, the Firebase CLI is not used, and the Firebase project and Android apps are created through the Firebase Management REST API (https://firebase.googleapis.com/v1beta1/) with the access token of gcloud auth print-access-token. The agent confirms the exact requests from Google's official API reference at implementation time.

1. HUMAN: gcloud auth login on the Mac with the owner's Google account.
2. gcloud config set project kvitt-1337; gcloud services enable fcm.googleapis.com firebase.googleapis.com.
3. Add Firebase to the project (projects.addFirebase), skipped if it is already a Firebase project.
4. Create two Android apps (projects.androidApps.create): display name "Kvitt", package se.hagstedt.kvitt; display name "Kvitt debug", package se.hagstedt.kvitt.debug.
5. Fetch each app's config (projects.androidApps.getConfig) and merge them into one google-services.json holding both clients, written to infra/secrets/google-services.json in the main checkout (git-ignored). M8 copies it into android/app/google-services.json (git-ignored) with infra/dev/copy-google-services.sh <main checkout>, written by M2c-dev.
6. gcloud iam service-accounts create kvitt-fcm --display-name "Kvitt FCM sender"; grant roles/firebasecloudmessaging.admin on the project; gcloud iam service-accounts keys create infra/secrets/fcm-service-account.json --iam-account kvitt-fcm@kvitt-1337.iam.gserviceaccount.com.
7. Copy the key to ~/kvitt/secrets/fcm-service-account.json on the Pi, owned by the owner, mode 0600 (D-125; was /opt/kvitt/secrets/, mode 0440, root:10001, installed by install.sh, D-103). Done by the owner (infra/README.md "Pi: what the owner does", steps 2 and 3).
8. If an organisation policy blocks service-account key creation, stop and report; do not change org policies.

The agent may write these git-ignored files under infra/secrets/ in the main checkout and act on the Google Cloud project kvitt-1337 for steps 2 to 6 (D-022); nothing else outside the repository.

State after M2c-dev (c885aba): steps 1 to 6 are done. Firebase is added to project kvitt-1337; Android apps exist for se.hagstedt.kvitt and se.hagstedt.kvitt.debug; the APIs firebase.googleapis.com, fcm.googleapis.com, cloudresourcemanager.googleapis.com and iam.googleapis.com are enabled; the service account is kvitt-fcm@kvitt-1337.iam.gserviceaccount.com with role roles/firebasecloudmessaging.admin (a role named roles/firebasemessaging.admin does not exist); infra/secrets/fcm-service-account.json and infra/secrets/google-services.json (both clients) exist in the main checkout. infra/README.md documents the REST calls for repeating or inspecting the setup. Step 7 is part of the owner's install on the Kvitt Pi (checklist steps 2 and 3, D-125).

The FCM free tier is sufficient; no billing account is required.

10.8 Splitwise import

Command (run on the Pi with the server stopped, or on the Mac against a copy of the database):

kvitt-import --db /data/kvitt.sqlite --file <csv> --account "<Kvitt account name>" \
  --user "<Splitwise name of the owner>=<owner user id or display name>" \
  --user "<Splitwise name of the partner>=<partner user id or display name>" \
  [--fx <CUR>=<SEK per unit>]... [--dry-run]

• One CSV file per Splitwise group (Splitwise's group "Export as spreadsheet"). The account is created with default 50/50 if no non-deleted account with that name exists; otherwise rows go into the existing one, and the existing account's stored name (not the spelling given to --account) is the account name used in the import key (D-046).
• --user (exactly two, distinct Splitwise names, one per household user) maps a member column to a Kvitt user given as a user id or as a display name that exactly one user has; anything else is a usage error (D-046).
• The importer never creates or migrates a database: --db must name an existing file whose meta.schema_version is the version the server's migrations produce (3 since D-090; 2 from D-054), else it exits 1 (run kvitt-server migrate first) (D-046, D-054).
• The whole run is one BEGIN IMMEDIATE transaction: find or create the account, skip rows whose import_key exists, validate and insert the rest with the server's own push checks, write the audit entries, then reconcile (below). It commits only when every row is valid, the reconciliation is accepted and --dry-run is absent; otherwise it rolls back and nothing is written. A dry run runs the same transaction and rolls it back (D-046).
• Exit status (D-046): 0 imported (or, with --dry-run, would import); 1 database or file error; 2 usage (bad arguments, --user not resolving to the two household users); 3 the file cannot be imported (header, invalid rows, non-SEK rows without --fx); 4 reconciliation mismatch or missing totals row. Nothing is written unless the status is 0 and --dry-run is absent.
• Header (confirmed against both real exports, D-003; the exact header lines are recorded in PLAN-M9, not here): Splitwise localises the export, so two variants exist and the importer must accept both. English: Date, Description, Category, Cost, Currency; Swedish: Datum, Beskrivning, Kategori, Kostnad, Valuta. Then one column per group member, named by the member's full Splitwise name, holding that member's net effect for the row (positive = paid more than their share). The member columns appear in different orders in different files, so the importer reads member names from the header and matches them to the --user arguments; it never relies on column positions. Any other header fails the import with a clear message, writing nothing.
• Fields containing commas are double-quoted (CSV quoting). The file ends with an empty line followed by a row whose Description is Total balance (English) or Totalsumma (Swedish), the totals row, holding each member's balance; it creates no row and is used only for the reconciliation. Blank rows are ignored.
• Reconciliation (D-045): after the rows are written, inside the transaction, each user's balance of the whole account (net(u), §9.3, over every non-deleted row of the account, not only the imported ones) must equal the sum of that member's values in the file's totals rows. One totals row is allowed per currency; a non-SEK totals row is converted with the --fx rate like any other value. A mismatch, or a file without a totals row, rolls the run back and exits 4; a dry run reports the same. Importing into an account that already holds other rows therefore rolls back, since those rows enter the comparison. When any --fx conversion took place, per-value rounding can make an exact match impossible, so a mismatch is reported in the summary but accepted. A re-run of an already imported file skips every row and reconciles again on the same balance.
• Date is YYYY-MM-DD; Cost and member columns are decimal numbers with . as separator, converted to öre exactly by string parsing.
• For each expense row with members A and B and cost C (öre): the payer is the member with positive net. If net_A > 0: payer A, share_B = net_A, share_A = C − net_A, mode exact. Symmetric for B. If both nets are 0: payer is the owner, mode full on the owner (the owner pays and bears the whole cost, D-046). If net_A + net_B ≠ 0 or a resulting share is negative, the row is reported as invalid and the import aborts (nothing written).
• Rows whose Category is Payment (English) or Betalning (Swedish) become settlements: from = the member with positive net, to = the other, amount = that net, one allocation to the account, note = the Splitwise description truncated to 200 code points (D-046).
• Rows whose Currency is not SEK abort the import unless a --fx <CUR>=<rate> is given for that currency; then every amount is converted with round_half_up(amount_ore × rate) per value, and for expenses the exact shares are recomputed as share_payer = C' − share_nonpayer'.
• import_key = lowercase hex SHA-256 of splitwise|v1|<account name>|<Date>|<Description>|<Category>|<Cost>|<Currency>|<member nets in header order, joined with |>|<n> where <n> is the 0-based occurrence index of an identical line earlier in the same file. Rows whose key exists are skipped. Idempotency uses the existing import_key columns of expenses and settlements (§14.1); no new column or table (D-046).
• Every created row: created_by_user_id = updated_by_user_id = the owner; updated_by_device_id null; created_at = updated_at = the import time; one audit entry create with source = import; new server_versions from the global sequence; no pushes.
• Description is truncated to 100 code points; the full original goes into notes when truncated. An empty description, or one over 1000 code points (the notes limit, §9.6), makes the row invalid (exit 3, nothing written) (D-046).
• Category mapping (case-insensitive exact match on the Category column, English and Swedish names, D-003). The importer commits this table as the data file server/crates/kvitt-import/data/splitwise_categories.csv (columns splitwise_name,language,default_key) and reads it from there; it is the only mapping. Splitwise categories are mapped as finely as the fourteen categories of AC-7.2 allow (D-053); the Swedish names are those observed in the real Swedish export, each placed with its English Splitwise equivalent (D-044, D-053):

Splitwise category (English)	Splitwise category (Swedish)	Kvitt default_key
Groceries, Food and drink - Other, Liquor	Livsmedel, Mat och dryck - Övrigt, Alkohol	groceries
Dining out	Restaurangbesök	restaurants
Rent, Mortgage	Hyra, Avbetalning/Amortering	housing
Electronics, Furniture, Household supplies, Maintenance, Services, Pets, Home - Other	Elektronik, Möbler, Förbrukningsvaror, Skötsel/underhåll, Tjänster, Husdjur, Hem - Övrigt	home
Electricity, Heat/gas, Water, Trash, TV/Phone/Internet, Cleaning, Utilities - Other	El, Värme/gas, Vatten, Sophämtning, TV/telefon/internet, Städning, Verktyg - Övrigt	utilities
Insurance	Försäkringar	insurance
Bicycle, Bus/train, Car, Gas/fuel, Parking, Taxi, Transportation - Other	Cykel, Buss/tåg, Bil, Bensin/bränsle, Parkering, Taxi, Transport - Övrigt	transport
Hotel, Plane	Hotell, Flyg	travel
Games, Movies, Music, Sports, Entertainment - Other	Spel, Filmer, Musik, Sport, Underhållning - Övrigt	entertainment
Medical expenses	Sjukvård/medicin	health
Childcare	Barnomsorg	children
Clothing, Gifts	Kläder, Presenter	shopping
Taxes	Skatter	fees
General, Education, Life - Other, Other	Allmänt, Utbildning, Livet - Övrigt	other
any other value	any other value	other, counted as unmapped

The Swedish names El, Värme/gas, Vatten, Sophämtning and Husdjur were not seen in the export; they are Splitwise's Swedish labels by analogy (D-053). A wrong guess only leaves such a row unmapped (other, counted), which the summary shows.

• The summary lists each unmapped category name with its row count, and the total count of unmapped rows as a warning.

Production run (M11, D-025), in this order:

1. On the Pi in ~/kvitt (D-125), take a backup first: docker compose exec backup /backup.sh (it ends with backup: ok <stamp> once both files are confirmed on Drive with rclone lsf).
2. Resolve the two production user ids by display name from the database (a read-only SELECT id, role, display_name FROM users through the backup container's sqlite3); the owner is the admin user. The ids go into the --user arguments (an exact, unique display name is also accepted, D-046).
3. Copy the CSV files from the Mac to the Pi into ~/kvitt/import/ (/home/jacobhagstedt/kvitt/import/; scp <file> jacobhagstedt@<kvitt-pi-address>:kvitt/import/), which is bind-mounted read-only into server as /import (§10.2, D-125; was /opt/kvitt/import/).
4. docker compose stop server; for each file run docker compose run --rm --entrypoint kvitt-import server --db /data/kvitt.sqlite --file /import/<file> --account "<name>" --user "…" --user "…", first with --dry-run, then without; each must exit 0 with the reconciliation match (D-045); the target accounts must not exist yet or be empty; docker compose start server; check /health. (--entrypoint is needed because the image's entrypoint is kvitt-server, §10.3.)
5. Delete the CSV files from ~/kvitt/import/.

10.9 Backups and restore

Backup (infra/backup/backup.sh, daily 03:30 Europe/Stockholm, also runnable on the Pi in ~/kvitt as docker compose exec backup /backup.sh, which ends with backup: ok <stamp> when the run succeeded; backup-now.sh is removed, D-125):

1. sqlite3 /data/kvitt.sqlite ".backup /backups/staging/kvitt.sqlite" (online, consistent).
2. sqlite3 /backups/staging/kvitt.sqlite "PRAGMA integrity_check" must print ok, else abort with a log line.
3. gzip -9 to /backups/kvitt-<UTC yyyyMMddTHHmmssZ>.sqlite.gz; tar -czf /backups/pictures-<same stamp>.tar.gz -C /data pictures.
4. For every pending kvitt-*.sqlite.gz and pictures-*.tar.gz in /backups (this run's pair and any leftovers of an earlier failed run): rclone copy <file> "${RCLONE_REMOTE}" --drive-root-folder-id "${RCLONE_FOLDER_ID}" --immutable (copy only; never sync, never delete, never overwrite), then confirm it by name and size with rclone lsf (D-106). rclone uses a temporary copy of the read-only rclone.conf (D-105). The snapshot is the whole database, so it includes the card tables of migration 0004 (connections with their Enable Banking session ids, purchases, attempts; D-161): the backups on Drive therefore hold the users' card purchases, unencrypted like the rest (accepted risk M-1, §8.1). The Enable Banking private keys are in secrets/cards/, not data/, and are never backed up; a restore needs them copied again from the Mac (infra/secrets/cards/).
5. Only after every file is confirmed are the local copies deleted from the Pi's backups/ folder (D-002), and only then is /backups/last-success written with the stamp (D-106). A failed upload or confirmation keeps the local files and leaves last-success unchanged; the next good run uploads the leftovers. Nothing on Drive is ever deleted. When RCLONE_FOLDER_ID is empty (the development stack, D-001), step 4 is skipped with a log line, the local files are kept and last-success is written.

rclone setup (HUMAN, once, done 2026-10-18): the owner ran rclone authorize "drive" and signed in; the token (infra/secrets/rclone-drive-token.json) became infra/secrets/rclone.conf with a [gdrive] remote (type = drive, scope = drive, token), both git-ignored. The owner copies it to ~/kvitt/secrets/rclone.conf on the Pi, mode 0600 (§10.2, D-125); the folder id stays in .env as RCLONE_FOLDER_ID, not in the conf. The Drive destination root folder id is 1jDp1dGE5R3H2DBcXCqIPN1iWzQnPkdlV (OQ-4, answered); it is the value of RCLONE_FOLDER_ID in the Pi's .env.

Restore (step by step in infra/RESTORE.md, run on the Pi in ~/kvitt as the owner, D-125). The files in data/ and backups/ are the owner's (both containers run as the owner's uid), so they are moved on the host with plain mv, cp, gunzip and tar; only rclone (listing and downloading from Drive, on a temporary copy of rclone.conf) and sqlite3 (PRAGMA integrity_check) run in the running backup container. Nothing is deleted. Not around 03:30, when the nightly backup runs.

1. docker compose stop server.
2. Download the chosen kvitt-*.sqlite.gz and pictures-*.tar.gz from Drive into backups/restore/ (rclone in the backup container, or the browser and scp from the Mac).
3. gunzip on the host; docker compose exec -T backup sqlite3 /backups/restore/<file> "PRAGMA integrity_check" must print ok.
4. Move the current data/kvitt.sqlite, -wal, -shm and data/pictures aside into data/pre-restore-<UTC stamp>/ (never delete), copy the restored file to data/kvitt.sqlite, extract the pictures into data/.
5. docker compose run --rm server rotate-epoch.
6. docker compose start server; docker compose ps server healthy; curl -fsS http://localhost:8080/health.
7. Open the app on both phones; they detect the new epoch and re-push their data (§14.4.8). Check the balances match on both phones.
8. Afterwards, docker compose exec backup /backup.sh once puts the restored state on Drive.

10.10 Operations

• Where: every command on the Pi in this section is run by the owner in ~/kvitt (/home/jacobhagstedt/kvitt) with plain docker compose (D-125, revises D-103's scripts); the owner's operations table is in infra/README.md "Pi: what the owner does", Operations. Agents prepare and check the project on the Mac and never connect to the Pi (D-100).
• Status and logs: docker compose ps; docker compose logs --tail 100 <service>; NPM's own log files are inside NPM on the Home Assistant Pi (§10.5.2).
• Disk: df -h ~ and du -sh ~/kvitt/*. SQLite is a few MB; pictures under 1 MB; APKs about 10 MB each since R8 (§10.6), older ones removed by hand.
• Deploy (upgrade), after infra/build-images.sh v1.0.N on the Mac pushed the images (D-211; or the Gitea workflow, the fallback, pushed a v1.0.N tag): docker compose exec backup /backup.sh first, continuing only after backup: ok, on every deploy, because the Pi cannot tell beforehand whether a tag carries a migration (D-103, kept by D-125); then set KVITT_TAG in .env (sed -i 's/^KVITT_TAG=.*/KVITT_TAG=v1.0.N/' .env, noting the previous tag), docker compose pull && docker compose up -d, and check docker compose ps and curl -s localhost:8080/health. Migrations run on start; a failed migration exits non-zero and the container restarts in a loop.
• Rollback: set the previous KVITT_TAG in .env and docker compose pull && docker compose up -d (no previous-tag file and no --skip-backup since D-125). Migrations are forward-only, so if a migration had partially applied, restore the pre-deploy backup (§10.9, infra/RESTORE.md); sqlx runs each migration in a transaction, so this should not happen.
• Bootstrap and invites: docker compose exec server kvitt-server bootstrap (first install only: the admin invite code, link and expiry of FR-1); once the admin is paired, the partner's invite docker compose exec server kvitt-server invite-partner; an extra device docker compose exec server kvitt-server pair-device --user <user_id> (§10.4).
• Memory check: docker stats --no-stream after the release milestone; server RSS must be under 100 MB with both phones syncing.
• Image digests (D-117 point 5, revised by D-125): the Pi keeps no digest record. After a pull, docker image inspect --format '{{.RepoDigests}}' gitea.lan/jacobh2/kvitt-server:<tag> (and kvitt-backup) prints the sha256: digest, which the owner compares with the workflow's "Print image digests" step for that run (§10.3); the registry is plain HTTP on the LAN (security review L-9), so a mismatch is investigated before the stack is trusted.
• Client IPs (once, after the NPM proxy host and the router check, D-117, D-120, D-124): with the phone off Wi-Fi, open the app's About screen (S-22; before the app gate of D-126, https://<KVITT_PUBLIC_HOST>/health in Chrome does as well), then within a minute on the Kvitt Pi sudo conntrack -L -p tcp --orig-port-dst 8080 (package conntrack, installed once): in every line the first src= is HA_HOST and the reply half (from the second src=) has dst=<HA_HOST> with no 172.* address, so the server sees NPM's address and trusts its X-Forwarded-For; a 172.* address there means every internet client shares one per-IP limit of §8.6 (security review I-5; the commands are in infra/README.md's operations table).
• Health from outside (D-126): the app's About screen (S-22) on the phone with Wi-Fi off shows the server version, or curl -fsS -H "X-Kvitt-App: $KEY" https://<KVITT_PUBLIC_HOST>/health from outside the home network; without the header the connection is closed (§8.5).
• Card purchases (D-175, K1 writes the runbook entry in infra/README.md): the private key files live in ~/kvitt/secrets/cards/ (mode 0600, the folder 0700), copied from infra/secrets/cards/ on the Mac; the application ids in .env. Status: docker compose logs server | grep card_fetch shows the aggregate lines of §8.7. Every 180 days at most (CP-6) each user renews with BankID in the app; nothing on the Pi changes.
• Headers through NPM (after the first setup and after every NPM upgrade): curl -sS -D - -o /dev/null --resolve <KVITT_PUBLIC_HOST>:443:<HA_HOST> https://<KVITT_PUBLIC_HOST>/health lists content-security-policy, x-content-type-options, x-frame-options, referrer-policy and strict-transport-security once each and no x-served-by (§10.5.2).

---

11. Milestones

Each milestone is one plan (PLAN-<id>.md, written by the orchestrator's plans agent from this section) run by one Opus agent in its own worktree, unless the row says otherwise. "Gate" is what must pass before landing. The Android gate is tools/gradle-serial.sh check; the server gate is cargo fmt --check && cargo clippy --all-targets -- -D warnings && cargo audit && cargo test in server/; the web gate (D-131, §15.3) is npm run check in web/; "both gates" means the Android and server gates. HUMAN steps are what only the owner can do.

11.1 Dependency graph

M0 spec ──┬─► U1 directions ─(owner picks)─► U2 design spec ─► §9.7 colours ─► M6 design ─► M7a..M7f features ──┐
          │                                                                                                     │
          ├─► M1 contracts + vectors ─┬─► M2a server skeleton + domain ─┬─► M3 server core API ───────────┐       │
          │                           │                                 ├─► M4 server sync/audit/push ─┬──┤       │
          │                           │                                 │                              └──┼─► M9 importer
          │                           └─► M2b android skeleton + domain ┴─► M5 android data layer ───────┼───────┤
          │                                                                                               │       ▼
          └─► M2c-dev infra for development (Mac compose, Firebase, local backup) ─────────────────────┴──► M8 app integration
                                                                                                                  │
                                                     M2c-pi infra on the Pi (Pi, TLS, Gitea, router, Drive) ◄─────┤
                                                                              M10 first release ◄── M2c-pi, M8 ◄──┘
                                                                              M11 import real history ◄── M9, M10

Category contract v2 (D-054), after SPEC v0.8:
M12a contracts + :domain suggestCategory (landed aa765bb) ─┬─► M12b server (migration 0002, importer table; landed 6eaccec)
                                                            └─► M12c android (:core:model, :domain, :data, fakes; landed b09f322) ─► M6, M7c
M12d UI contract additions (D-059: frequentCategoryIds, deletable; landed 557af7e) ─► M7a..M7f   (ran in parallel with M6, landed 7730a31)

After the M7 wave (v0.11):
M7a..M7f (landed) ─► M6b core:design fixes (landed b24c8b5) ─┬─► M8 app integration (landed 3d9eea8)
                                                            └─► M7g feature cleanups (landed 3dda414)

After M8 (v0.13):
M8, M7g (landed) ─► M12e contract pass (landed 8c60715 and b7b7483; D-086 to D-095, server schema 3)

After the first phone test (v0.15):
M8 phone test (2026-10-18) ─► M8b UI fixes (landed 328c466, D-097) ─► M2c-pi bundle (D-100), last, after the app is proven ─► M10

After v0.15 (v0.16):
M8b ─► M8c goldens and About (landed 75b549f, a0c25b0, 7c453d8; D-098, D-099) ─► M8d editor rows (landed bacbd18, D-102) ─► M8e (D-107)
R8 release build (landed c30a49e)

After v0.16 (v0.17):
M2c-pi bundle (landed 2476667, D-103 to D-106) ─► owner runs the bundle on the Kvitt Pi ─► M10
M8e S-19 option rows (landed a59abeb, D-107) ─► chips cleanup (landed 1328afe)
M8f instant navigation (landed 956908a, D-108)

After v0.17 (v0.18):
history rewrite and first push (18c527f) ─► infra overhaul (2fac1ec..e70fe0d) ─► server gap pass (landed 8660b7f, D-113)
security review (18c527f)   ─┬─► infra security (landed 7fb86f5, D-117)
AC-coverage audit (956908a) ─┼─► M12f Android follow-ups (landed dc7a296..a0259ab, D-109 to D-112, D-116)
                             └─► server overhaul (landed 8103dae..b985ce9; D-114, D-115) ─► router forward ─► M10

After v0.18 (v0.19):
M12f ─► Android overhaul (landed e4e6e5d..c582363, D-118) ─► push to origin (c582363) ─► owner runs the M2c-pi bundle ─► M10

Web client programme (v0.28, D-129 to D-134):
SPEC v0.28 ─┬─► W0 web foundation (web/**) ──────────┬─► W1 home, accounts ─┐
            │                                         ├─► W2 expenses, search, export
            │                                         ├─► W3 settle up       ├─► image build and deploy (§10.10)
            │                                         ├─► W4 analytics, insights (W-11 waits for W7)
            │                                         └─► W5 settings ───────┘
            └─► W7 server: /app/ serving, /analytics/* (D-135..D-138, v0.29) ─┬─► W4's W-11
                                                                               └─► W6 Android Insights

Card purchases (v0.35, D-158 to D-176; K0 done, v0.36; K1 landed `671c00d`, its report recorded in v0.38, D-181 to D-188; K2 landed `a8f91ee`, its report recorded in v0.39, D-191 to D-200; K3 landed `faeb752`, its report recorded in v0.40, D-201 to D-207):
SPEC v0.35 ─► owner steps (Enable Banking account, ToS, application, key, linked cards) ─► K0 local test app on the Mac
   ─► K0 report ─► SPEC v0.36 (K0's answers, D-177 to D-180) ────────┬─► K1 server (schema 4, adapter, E-36..E-44, poller, NPM text) ──┐ lands first
                                                                     ├─► K2 Android (:feature:cards, Room 2, Kortköp tab) ──────────┼─► lands after K1
                                                                     └─► K3 web (W-21..W-23) ────────────────────────────────────────┘ lands after K2 (card strings)

After M1, M2a and M2b land, these run in parallel without touching each other's files (§14.7): M3, M4 (lands after M3, D-015), M5, M2c-dev, M6 (once U2 is approved and the §9.7 colour change from U2's proposal has landed in this spec), M7a to M7f (once M6 lands), M9 (once M4 lands). M2c-pi runs after M8 and before M10 (D-001), as the last step once the app is proven on the phone against the development server (D-100). Group M12 "Category contract v2" (D-049, D-054): M12a first; then M12b and M12c in parallel; M6 and M7c wait for M12c (all three landed: aa765bb, 6eaccec, b09f322). M12d (D-059) ran in parallel with M6 (landed 557af7e and 7730a31); M7a to M7f ran in parallel and landed on 2026-10-18 (1ea752c, 0e1d99d, 0b140aa, 7380e50, ea7d494, c4ab35f), followed by M6b, the :core:design fix pass (b24c8b5). M8 and M7g (feature cleanups) ran in parallel (disjoint paths: android/app/** and android/adapter/fcm/** against android/feature/**) and landed on 2026-10-18 (3dda414; cb832a7 and 3d9eea8). The contract pass M12e (D-086 to D-095) ran after them and landed on 2026-10-18 (8c60715 contract pass, b7b7483 launcher icon). The M2c-pi bundle (2476667, D-103 to D-106), M8e (a59abeb, D-107) and M8f (956908a, D-108) landed on 2026-10-18; what remains of M2c-pi is the owner running the bundle, and M10 waits for it.

11.2 Milestone table

Id	Name	Deliverable	Gate	HUMAN	Depends on
M0	Spec v0.1	SPEC.md, filled CLAUDE.md, repository bootstrap	none (docs only)	Review the spec; answer §12	none
U1	UX directions	Landed 6da6b1b (direction 3 "Kalas" muted picked, D-047). §13.4 phase 1 files in docs/ux/	Files exist and open; each direction shows the six phase-1 screens of §13.4 (S-4, S-7, S-5, S-9, S-11, S-8) in light and dark; Swedish copy, no placeholder text	Review 2-3 directions, pick one, give comments	M0
U2	UX design spec	Landed 6da6b1b, approved by the owner: docs/ux/design-spec.md (binding, §13.4), strings.csv (558 rows), screens/; UX-9 (D-059). §13.4 phase 2 files in docs/ux/	Every string key has en and sv; every screen has every state that design-spec.md lists for it (§13.3)	Approve the design spec	U1 and the owner's pick
M1	Contracts and vectors	contracts/openapi.yaml, contracts/schema/server-v1.sql, contracts/test-vectors/*.json, contracts/examples/**/*.json, tools/contracts-check.py	python3 tools/contracts-check.py passes: all JSON parses, every vector file matches §14.5.5, a stdlib-only Python reference of §9.1, §9.3, §9.4 reproduces every expected value, every example validates against the shapes of §14.3 by key set	none	M0
M2a	Server skeleton and kvitt-domain	Cargo workspace, three crates, config, DB pool, migration 0001_init.sql byte-identical to contracts/schema/server-v1.sql, error type with every §14.3.2 code, auth extractor (§8.2), all routes of §7 registered with handlers returning 501 not_implemented, utoipa document equal to contracts/openapi.yaml, GET /health and GET /setup/status implemented, kvitt-domain passing all vectors plus next_occurrence_date, server/Dockerfile; shell files in M3, M4 and M9 paths (D-004); the seams of §6.3 (D-015)	Server gate (includes the OpenAPI match test, the migration identity test, the vector tests)	none	M1
M2b	Android skeleton and :domain	Gradle project in android/ with every module of §6.2, version catalog, architecture check, :core:model types and repository interfaces of §14.2.4, :domain passing all vectors (including analytics), :core:fakes with the empty scenario (§6.2, D-018) for each repository, the Room 3 entities of §14.2.1 and §14.2.2 and KvittDatabase version 1 in :data with the exported schema (D-012), screenshot tests with Roborazzi (D-010), module shells for every module with one empty entry composable per feature (D-004), the feature convention of §6.2 in build-logic (D-017), :app launching to an empty themed screen, :app string files with the app name only in both languages, lint MissingTranslation as an error in every module	Android gate	Plug the phone in once to confirm installDebug works	M1
M2c-dev	Infra for development (D-001, D-022)	Landed c885aba. infra/dev/compose.yaml (server built from server/Dockerfile, no Caddy, no TLS, bind-mounted data, infra/secrets/ mounted read-only at /secrets, backup runnable on demand), infra/dev/.env.example, the dev scripts in infra/dev/ (build, up, logs, backup, copy-google-services.sh), infra/README.md (dev stack and Firebase), infra/backup/{Dockerfile, backup.sh} (Drive upload skipped when RCLONE_FOLDER_ID is empty), Firebase project and apps through the REST API (§10.7), service-account key and google-services.json in infra/secrets/	docker compose -f infra/dev/compose.yaml --env-file infra/dev/.env.example config succeeds; shellcheck $(find infra -name '*.sh') clean; on the Mac (with the M2a image): GET /health answers 200 from the Mac; one local backup run produces a snapshot that passes PRAGMA integrity_check	gcloud auth login; on the phone on the home Wi-Fi, open the dev server's /health and answer yes/no that it shows "status":"ok"	M0 (uses the M2a image for the health check when available)
M2c-pi	Infra on the Pi (D-001, D-100, D-120, D-125)	Bundle landed 2476667 2026-10-18 (D-103 to D-106); the NPM rework (D-120: 4f69ae0 workflow login, d05f13a stack without Caddy and cert-sync, 62f5279 and 9231a1d README) landed 9231a1d 2026-10-19; port 443 (D-124: 4852803 bundle) landed 2026-10-19; the sparse-checkout workflow (3820f9c, 2026-10-19), the .env without the informational keys (200c99f, 2026-10-20) and the self-contained compose project (D-125, 6e5981d, 2026-10-20) landed. The NPM proxy host for kvitt.suorra.duckdns.org is Online with its Let's Encrypt certificate (owner, 2026-10-19); the Gitea workflow built and pushed v1.0.0 (run 69) and v1.0.1 (§10.3); the owner is installing on the Kvitt Pi (2026-10-20). Deliverable: a self-contained compose project in infra/pi/ (compose.yaml, .env.example, .gitignore) that the owner copies to /home/jacobhagstedt/kvitt on the Kvitt Pi and runs with plain docker compose commands (D-100, D-125): server and backup as the owner's uid, the seven .env keys, relative bind mounts ./data, ./backups, ./import (§10.2); a README checklist for the owner (infra/README.md "Pi: what the owner does": prerequisites, .env and secrets on the Mac and the copy, start, the NPM proxy host and its Custom Nginx Configuration of §10.5, the router check (external 443 → Home Assistant Pi 443, no new rule, D-124), from outside, first backup and bootstrap, deploy), infra/RESTORE.md, Drive backups to folder id 1jDp1dGE5R3H2DBcXCqIPN1iWzQnPkdlV, Gitea Actions image build from the owner's example workflow in .gitea/workflows/	On the Mac: docker compose -f infra/pi/compose.yaml config succeeds with the env template (D-103); shellcheck $(find infra -name '*.sh') clean. Green at D-125 (2026-10-20): compose config valid; a Podman rehearsal of the project folder as uid 501 (not 10001): both containers healthy with read-only roots, /health 200 with db_ok: true, the database files and data/apk owned by 501 on the host, kvitt-server bootstrap through exec, an APK and latest.json copied into data/apk/ served at once, /backup.sh in three modes (no folder id: files kept, last-success written; a local remote: uploaded, confirmed, local copies deleted; a failing remote: files kept, last-success unchanged), the RESTORE.md steps ending with /health 200. Still valid from the NPM rework: nginx -t of the §10.5.2 block against NPM v2.16.0's templates and the 21 checks of the server behind nginx (§10.5.2). Not verifiable from the Mac: NPM's UI and Let's Encrypt for the Kvitt host name, the router forward, pulls from gitea.lan, Docker Compose itself (create_host_path: false, which Podman ignores), Drive. On the Pi, run by the owner from the checklist: docker compose ps shows both services healthy and curl localhost:8080/health answers ok; https://<KVITT_PUBLIC_HOST>/health answers from the phone on mobile data without a certificate warning; one backup pair appears in the Drive folder	Fill infra/pi/.env on the Mac (HA_HOST; check KVITT_UID/KVITT_GID and KVITT_TAG), copy compose.yaml, .env and secrets/ to ~/kvitt on the Kvitt Pi and run the seven steps of infra/README.md "Pi: what the owner does" (prerequisites, Mac, start, NPM, router check, from outside with first backup and bootstrap, deploy), answering yes/no per check. Done: the Drive token (rclone.conf), the example workflow, the Gitea secret kvitt_cicd (renamed by the owner 2026-10-19; run 69 succeeded), the Kvitt host name kvitt.suorra.duckdns.org and its NPM proxy host (2026-10-19), Docker and the registry trust on the Pi (prerequisites). No allowances for agents on the Pis, Home Assistant, NPM, Gitea or Drive (D-100)	M2c-dev, M8; runs last, after the app is proven (D-100)
M3	Server core API	Landed 7869ec4 (D-030 to D-034). E-3 to E-30 and E-33 implemented (§14.3; E-2 is M2a's, M3 tests it), invite landing page, pictures, rate limiting (src/api/rate_limit.rs), bootstrap, pair-device, the recurring generation function of §6.3 (D-015)	Server gate; integration tests per endpoint and per error code listed for it; every generation case of §9.5 (catch-up, clamping, split resolution, idempotency, resume without backfill, next_occurrence_date)	none	M2a
M4	Server sync, audit, push, scheduler	Landed 15056dc (D-035 to D-039). E-31, E-32, the real AuditWriter (writer and diff) and PushQueue (FCM sender), src/tasks/** starting them, sync_mutations pruning daily at 04:00 (D-021), scheduler, rotate-epoch	Server gate; integration tests for every sync rule of §14.4 and the scheduler cases of §9.5 (run at start, daily 06:00 on DST days, catch-up through M3's generation function); FCM sender tested against a local stub HTTP server	none	M2a; lands after M3 (D-015)
M5	Android data layer	Landed 8f0e156 (D-026 to D-029, D-040 to D-043). DAOs on M2b's Room 3 entities and KvittDatabase v1 (§14.2, D-012; any change to the entities or the exported schema is a contract change, §14.8), Ktor client and DTOs, token store, sync engine and workers, real repositories, APK updater	Android gate; DTO round-trip tests over every file in contracts/examples/; sync engine tests with Ktor MockEngine covering §14.4 including the 14-day offline case (AC-15.6)	none	M1, M2b
M12a	Category contract v2: contracts	Landed aa765bb. contracts/category-keywords.csv (148 entries), contracts/schema/migrations/0002_categories_v2.sql (§14.1.1), contracts/test-vectors/suggest_category.json (65 cases), E-1 example schema_version 2, tools/contracts-check.py (keyword-table rules, 0002 loaded on a fresh and an in-use v1 database, Python reference of §9.11, new icon and colour tokens), and :domain's suggestCategory with UnicodeText passing the vectors (§14.5.6). The OpenAPI DefaultCategoryKey extension and the new category examples were held back for M12b	python3 tools/contracts-check.py passes	none	M1, SPEC v0.8
M12b	Category contract v2: server	Landed 6eaccec (D-057, D-058). Migration server/crates/kvitt-server/migrations/0002_categories_v2.sql byte-identical to the contract file with its identity test; SCHEMA_VERSION 2; seed test of the fourteen defaults (ids, keys, icons, colours, sort orders, server_version from the sequence) on a fresh database and on a v1 database holding expenses (rows and references kept); icon and colour lists of §9.7 in validate.rs; DefaultCategoryKey with the fourteen keys in contracts/openapi.yaml (held back by M12a) and in the utoipa wire types, so the OpenAPI match test passes; the category examples M12a held back; importer table splitwise_categories.csv per §10.8 with its spec-parity test; importer schema check 2 (D-054); E-31 and other examples only where they enumerate the defaults	Server gate; python3 tools/contracts-check.py passes	none	M12a, M3, M4, M9
M12c	Category contract v2: Android	Landed b09f322 (D-055 to D-057). :core:model: DefaultCategoryKey (14), ColorToken (SLATE, AMBER), CategoryIcons.ALL (33), ExpenseRepository.suggestCategory; :data: the UnicodeText binding (java.text.Normalizer, Character), suggestCategory from Room, DataStore and the keyword table copied from contracts/category-keywords.csv at build time (D-055; a test asserts byte identity and the §14.8 rules), parsed by :domain's parseCategoryKeywords (D-056); :core:fakes: fourteen defaults in the empty scenario and a fake suggestCategory; default-name string resources for the four new categories in English and Swedish (AC-7.2) where default names already live	Android gate	none	M12a, M2b, M5
M12d	UI contract additions (D-059)	Landed 557af7e (D-060 to D-062). :core:model: ExpenseEditorOptions.frequentCategoryIds and CategoryRepository.deletable(id) (§14.2.4 "Changes in v0.9"); :data: both computed from Room, with repository tests; :core:fakes: both computed from each scenario's own data; ContractTest updated	Android gate	none	M12c, M5
M6	Design system	Landed 7730a31 (D-063 to D-066). Built from docs/ux/design-spec.md §2 and §3 and docs/ux/strings.csv. :core:design theme, tokens, typography (Material 3 default typeface, D-020), shared components including the ledger rows and expense editor fields (D-019), charts (Compose Canvas, D-063), formatters (§9.8), shared strings (including the notification copy) per docs/ux/design-spec.md and docs/ux/strings.csv, screenshot tests of every component in light and dark, Swedish and English	Android gate	Look at the component screenshots the agent opens and posts (yes/no)	U2, M2b, M12c, the §9.7 colour change
M6b	Design-system fixes after M7	Landed b24c8b5 (D-075 to D-079). :core:design fixes the M7 agents asked for: viewerPercentOf reads basis points, editor_split_full_on_you, AmountInput.of with both decimals and AmountInput.percent (D-078), quickRowCategories (D-075), two-line category labels with an ellipsis (D-076), DateFormatter.monthName and dayRangeLong (D-077), resource-backed snackbars in KvittScaffold, optional ConfirmDialog body, KvittButton loading form, InviteCodeField wrapping, EmptyState icon tile, AnalyticsFilterBar period row, screen tokens in KvittDimens, common_ok and common_undo, the module keys of M7b to M7f recorded in docs/ux/strings.csv (D-079)	Android gate	none	M7a to M7f
M7a	Feature: onboarding	Landed 1ea752c 2026-10-18 (D-071). :feature:onboarding screens S-1, S-2, S-3, S-18	Android gate with screenshot tests of every state, sv and en, light and dark	none	M6, M12d
M7b	Feature: home and account	Landed 0e1d99d 2026-10-18 (D-071). :feature:home, :feature:account screens S-4, S-5, S-6, S-16, S-17	as M7a	none	M6, M12d
M7c	Feature: expense	Landed 0b140aa 2026-10-18 (D-074, D-080). :feature:expense screens S-7, S-8, with the category suggestion of §9.11 (CS-2, CS-3, CS-7)	as M7a	none	M6, M12c, M12d
M7d	Feature: settle	Landed 7380e50 2026-10-18 (D-074). :feature:settle screens S-9, S-10	as M7a	none	M6, M12d
M7e	Feature: analytics	Landed ea7d494 2026-10-18 (D-069 to D-071). :feature:analytics screens S-11, S-12	as M7a	none	M6, M12d
M7f	Feature: settings	Landed c4ab35f 2026-10-18 (D-071 to D-073). :feature:settings screens S-13, S-14, S-15, S-19, S-20, S-21, S-22	as M7a	none	M6, M12d
M7g	Feature cleanups	Landed 3dda414 2026-10-18. Cleanups in android/feature/** after M6b; scope in its brief	as M7a	none	M7a to M7f, M6b
M8	App integration	Landed cb832a7 and 3d9eea8 2026-10-18 (D-081 to D-085). :app navigation and deep links (§13.2, D-071; each top-level screen draws its own bar), session gate (S-1 for Unpaired and Unrecognised, S-2, S-18 for Revoked, back on S-18 closes the app; Home shows S-3 while partner == null), deletion of the debug fakes module (both variants bind :data, D-081), :adapter:fcm with registration by Firebase Installation ID (D-083), push work and notification building (AC-13.5, D-085), invite links ignored while paired (D-084), ProvideHousehold as LocalKvittHousehold, LocalKvittClock from :data's Clock, LocalAvatarPictures handing the User to :data's Coil mapper, notification permission after the first successful sync after pairing (AC-2.9), update check in release only, revoke wipe, network security configs (§8.5, D-082), manifest hardening (§8.8), release signing and version properties (§10.6; unsigned without keystore keys), google-services.json copied with infra/dev/copy-google-services.sh	Android gate (green at landing: BUILD SUCCESSFUL, 710 actionable tasks); on the owner's phone against the development server on the Mac (D-001): pair, add an expense offline, reconnect, see it synced, receive a push (run on 2026-10-18 on the owner's S26 against the development server: pairing with the bootstrap code OK; a scripted partner joined through a second admin device paired with kvitt-server pair-device; Home showed the account; the offline expense showed the pending marker and synced after reconnect, pending 0, row on the server; the device registered fcm_token and app_version_name; a push by fid arrived and its tap worked). Follow-up M8b (landed 328c466, D-097) fixed what the test showed: the invite-code field, the quick-row badge, the status-bar inset of KvittTopAppBar, the chart corners; FcmMessageBody.fid in :data followed (6eb3f85, D-096)	Tap through the pairing, offline and push test as relayed by the orchestrator	M3, M4, M5, M7a-M7f, M2c-dev (Firebase, development server)
M12e	Contract pass	Landed 8c60715 and b7b7483 2026-10-18 (D-086 to D-095). The §11.3 contract requests of M5 to M8 taken together on both sides: E-3 invite_kind and Pairing (D-086); the admin's name in E-12 links, passed on by E-4 (D-087); SyncSummary.lastAttemptFailed (D-088); Rejection.actor (D-089); X-Kvitt-App-Version-Name, devices.app_version_name by migration 0003, server schema 3 (D-090); NewRecurringTemplate (D-091); UpdateCheck (D-092); SettleState.untouched (D-093); the D-027 re-stamp in :data (D-094); PushEvent in :core:model, snackbar hosts in six screens, snackbar resource ids from S-7 and S-8, the adaptive launcher icon (D-095). Goldens re-recorded: S-20 devices (version name); new s1_pairing_link_admin and s22_about_check_failed	Both gates (green at landing: Android BUILD SUCCESSFUL, 710 actionable tasks, 906 tests; server 253 tests, the OpenAPI equality, vector and migration byte-identity tests included)	none (the development server must be rebuilt before the new APK is installed, §14.8)	M8, M7g, SPEC v0.12
M12f	Audit and security follow-ups (Android)	Landed dc7a296, 5b2ed37, 2bd6b58, c366fbd, a0259ab 2026-10-18 (D-109 to D-112, D-116; no prompt file, orchestrator brief). S-16 read-only lost version (Rejection.lost, D-109); S-22 versions from /health (AboutState.schemaVersion, D-110); SettlementRepository without throws (D-111); E-17 retry (D-112); invite links dropped while paired (AC-2.6); private notifications (AC-13.9, D-116); localeFilters en, sv (AC-19.1); :data tests for the 429 retry, D-040 refusals and WorkManager unique work (work-testing, §6.2); the :feature:home and :feature:account screenshot harness fix (§6.2); the 19 string keys R8 found unused removed (strings.csv 562 rows, §13.4)	Android gate (green at landing, 941 tests); release APK 10.0 MB	Look at S-16 and S-22 on the next install (HANDOFF §3)	M8f, the AC-coverage audit and the security review (§11.4)
M9	Splitwise importer	Landed 50339ae (D-044 to D-046). kvitt-import per §10.8 with tests over synthetic CSV fixtures (crates/kvitt-import/tests/import.rs), reconciliation against the totals rows, the committed category table	Server gate	Provide the CSV files (kept outside git) when OQ-2 is answered	M2a, M4
M10	First release	Release build signed, published, both phones paired, push working both ways, nightly backup on Drive, restore drill report, memory check	docs/validation/first-release.md and docs/validation/restore-drill.md complete; server RSS under 100 MB	Create the release keystore with the keytool command of §10.6 at the repository root, or allow an agent to (D-101), and keep a copy and the password in the password manager; run the Pi steps of the M2c-pi compose project (D-100, D-125); install the APK on both phones from the landing page; allow "Install unknown apps"; partner pairs with the invite; confirm notifications arrive	M2c-pi (the owner's run of the bundle), M3, M4, M8
M11	Import history	Rehearsed on 2026-10-18: the real run reconciled on both files in a throwaway database (Vardag 1746 rows, Hemma 37 rows; 21 rows unmapped before D-044). Dry run of 2026-10-18 with the M12b mapping (D-053): Vardag 1746 rows, 0 unmapped; Hemma 37 rows, 0 unmapped; both reconciled. Real import run on the Pi per §10.8 "Production run" (D-025), docs/validation/splitwise-import.md with per-account totals compared to Splitwise's balances (aggregates only)	Imported balances equal Splitwise's "Total balance" rows per group	Provide the CSVs; confirm the balances on the phone match Splitwise	M9, M10
W0	Web foundation (D-131, D-134)	Landed 2ae65a5 (2026-10-21). web/: Vite, React 19, TypeScript strict, React Router 7, TanStack Query 5, openapi-typescript types in web/src/api/schema.d.ts and openapi-fetch, Vitest and Testing Library, ESLint and Prettier; design tokens from docs/ux/design-spec.md §2 as CSS custom properties; layout shell (sidebar, bottom bar under 720 px), router with every route of §15.3, keyboard shortcuts and W-20; login (W-1), token store and 401 handling; API client and household snapshot (§15.5); i18n (sv, en); formatting (§9.8); shared components; the money functions of §14.5.2 passing their vectors; npm run check	Web gate	none	SPEC v0.28
W1	Web: home and accounts	Landed 934eee7 (2026-10-21, D-144, D-145, SPEC v0.32). W-2, W-3, W-4 in web/src/features/{home,accounts}/	Web gate	Look at Home and an account in a browser against the development stack (yes/no); done on the Pi 2026-10-24 (D-211)	W0
W2	Web: expenses, search and export	Landed a65ab71 (2026-10-21, D-146 to D-148, SPEC v0.32; the shared editor fields in web/src/components/editor/). W-5 with the §9.11 suggestion (suggest_category.json, in the vector test since 83f5293), W-6 with the timeline, W-12 with the CSV export, in web/src/features/{expenses,search,export}/	Web gate	Add, edit and delete an expense in a browser; open an exported CSV in Numbers (yes/no); done 2026-10-24 (D-211)	W0
W3	Web: settle up	Landed f9a9bfb (2026-10-21, D-144, D-149, SPEC v0.32). W-7, W-8 in web/src/features/settle/	Web gate	Record and delete a settlement in a browser (yes/no); done 2026-10-24 (D-211)	W0
W4	Web: analytics and insights	Landed 1aecf51 (2026-10-21, D-151, D-152, SPEC v0.32). W-9, W-10 with the D-128 line chart, W-11 on the D-133 endpoints (E-34, E-35); resolveRange and spendSeries passing their vectors (features/analytics/domain/analytics.vectors.test.ts); in web/src/features/analytics/	Web gate	Look at the analytics pages in a browser (yes/no); done 2026-10-24, Insights included (D-211)	W0; W-11 needs W7
W5	Web: settings	Landed 3ebe57d (2026-10-21, D-153, D-154, SPEC v0.32). W-13 to W-19 in web/src/features/settings/	Web gate	Pair a browser, see it on the phone's Devices, revoke it from the phone (yes/no); done 2026-10-24 (D-211)	W0
W6	Android: Insights	Landed 1c9856b (2026-10-21, D-141 to D-143, SPEC v0.31; Android gate green, 40 s11_insights_* goldens). An Insights section on S-11 from the D-133 endpoints, online only (§9.9): a UI-contract change (§14.8) in :core:model, :data, :core:fakes and :feature:analytics, with goldens	Android gate	Look at S-11's Insights on the phone (yes/no); done 2026-10-24 against v1.0.3 (D-211)	W7 landed, its image deployed
K0	Card purchases spike: local test app (D-176)	The test app landed 2ce317f: docs/spikes/k0/app.py and its README.md, one command (python3 docs/spikes/k0/app.py, the standard library only, the RS256 JWT signed with openssl), a page on http://localhost:8765/ that runs the real Enable Banking flow (bank list, BankID, paste-back of the redirect address, accounts, "Uppdatera" with PSU headers, "Bakgrundshämtning" without, balances, the purchases, an aggregate "Analys", "Koppla från"), key and state in the git-ignored docs/spikes/k0/.local/. Done 2026-10-24: run with the owner on his card; report docs/spikes/K0-enable-banking.md (aggregates only), its answers recorded in SPEC v0.36 (D-177 to D-180); the partner's card and the next-day checks were not run (owner's decision, D-177) and move to K1's owner steps	The flow worked end to end with the owner's card (owner's yes); the report answers every K0 item; git status shows nothing from .local/; no gate (not part of any gate)	Done 2026-10-24: Enable Banking account and Terms of Service, the restricted production application, the key in .local/, the owner's card linked with BankID, the test app run (PLAN-K0 §8)	SPEC v0.35
K1	Card purchases: server (D-158 to D-175)	Landed 671c00d (2026-10-24; D-181 to D-188, SPEC v0.38). Migration 0004 with its contract text and migration test, server schema 4; src/cards/ (registry, Enable Banking adapter, the windowed fetch and de-duplication of §9.12 CP-7 and CP-8, poller, callback page); E-36 to E-44 in the server and contracts/openapi.yaml with examples; new error codes; the link clearing in §14.4.4 step 7; contracts/test-vectors/match_card_purchase.json and its Python reference in tools/contracts-check.py; config (§10.4), infra/pi/compose.yaml, .env.example, infra/dev/**, infra/npm/kvitt.conf, infra/README.md (step 4 block, card runbook); web/src/api/schema.d.ts regenerated	Server gate; python3 tools/contracts-check.py; the web gate (the regenerated types); an integration test suite against a local Enable Banking stub. At landing: server 356 tests (34 in tests/cards_api/), contracts-check 157 (17 match_card_purchase cases), web 609 (match_card_purchase listed as not ported until K3), the nginx check and both compose configs ok; the Android gate red by design until K2 lands (VectorFilesTest, ExampleRoundTripTest pin the contract's vector and example sets), so the commit bypassed the pre-commit hook (contract-first landing)	Copy the key (already on the Mac from K0) to ~/kvitt/secrets/cards/, set the application id in .env, paste the new NPM block, deploy; once a client with the card screens runs: the partner's card, the next-day fetch without BankID and pending→booked (D-177) (PLAN-K1 §8)	SPEC v0.36 (K0's answers)
K2	Card purchases: Android (D-169, D-170, D-172, D-173)	Landed a8f91ee (2026-10-24; D-191 to D-200, SPEC v0.39). :feature:cards (S-23 to S-27 and the sheet), Room version 2 with its migration test, the CardRepository UI contract in :core:model, matchCardPurchase in :domain passing its vectors, :data (DTOs, card sync, queued link changes, Custom Tab, deep link), fakes and scenarios, the fourth bottom destination, S-5's "Från kortköp", S-7's prefill and link, S-8's card line, the committed card artwork mapped (D-180), goldens; strings in docs/ux/strings.csv (77 rows); out-of-path edits ratified by the orchestrator: ArchitectureRules.kt knows cards, :core:design gains ic_credit_card / KvittIcon.CreditCard, the card measures in KvittDimens (D-200), the nav-label shrink-to-fit (D-197), StringsCatalogueTest takes cards_ as a feature prefix	Android gate. At landing: BUILD SUCCESSFUL, 791 actionable tasks, 1154 tests, 0 failures; the 11 card examples (E-36 to E-44) round-trip, the 17 match_card_purchase cases pass, VectorFilesTest and ExampleRoundTripTest green again on main; 150 goldens added (:feature:cards 135 for every state of S-23 to S-27 with _sv_light_200 for the long ones; S-5-account-menu-card, s7_from_card, s7_from_card_foreign, s8_from_card, s13_hub_card_connected) and 147 re-recorded for the fourth bar destination (S-3, S-4, S-11, S-13, S-17 and the navigation-bar component; only the bar changed)	Connect the card on the phone with BankID; create an expense from a purchase; link one; disconnect and reconnect (PLAN-K2 §8 steps 1 to 7, pending: the phone was not attached; the release APK with the card screens is installed by the orchestrator once K1's image runs on the Pi)	SPEC v0.36; may start then on the spec and fakes; lands after K1
K3	Card purchases: web (D-174)	Landed faeb752 (2026-10-24; D-201 to D-207, SPEC v0.40). W-21 to W-23 in web/src/features/cards/ (every §13.3 state but offline, the S-23 sheet actions, ?attempt= polling, ?account= as S-27), the Kortköp entry after Översikt in the sidebar and bottom bar, W-5's ?cardPurchase= prefill (CP-9) and link on save, W-6's card line with "Ta bort koppling", W-3's "Från kortköp", W-13's "Anslut kort" row, the committed card artwork mapped (D-180), the card snapshot in web/src/api/cards.ts, matchCardPurchase in TypeScript passing its 17 vectors	Web gate. At landing: web 70 files, 684 tests, build ok; contracts-check 157	Pending after image v1.0.5 is deployed: connect the card from the laptop browser with BankID QR; create and link from W-21 (PLAN-K3 §8, three steps)	SPEC v0.36; lands after K1 and K2 (it takes the card strings K2 adds to docs/ux/strings.csv)
W7	Server: web serving and analytics endpoints (D-132, D-133)	Landed 50a0d67 (2026-10-21, D-135 to D-138, SPEC v0.29; 299 server tests, contracts-check 136). /app/ from KVITT_WEB_DIR with the SPA fallback, cache headers and the /app/ CSP; the /analytics/* endpoints (D-135 to D-138, SPEC v0.29) in contracts/openapi.yaml and the server; the Node stage in server/Dockerfile with the repository root as build context (workflow, infra/build-images.sh, infra/dev/**)	Server gate; python3 tools/contracts-check.py; the web gate when web/ exists and the contract changed (web/src/api/schema.d.ts regenerated)	Paste the v0.28 NPM block (infra/README.md step 4); deploy the new image (§10.10); deployed 2026-10-24 as v1.0.3 (D-211)	SPEC v0.28

11.3 Notes per milestone

• M1 writes the OpenAPI file by hand from §14.3 (no code exists yet). M2a then annotates handlers so the generated document matches it; the equality test compares parsed values, not text (D-016), after the normalisations of §14.8 (D-005). M2a may change contracts/openapi.yaml only representationally (key order, $ref naming, description wording), listed in the plan report, with no spec bump (§14.8). Any semantic change follows the contract-change rule (§14.8). tools/contracts-check.py checks the file's header: OpenAPI 3.1.0, title Kvitt, version 1 and one server https://{host} whose variable host has the default kvitt.example.invalid (v0.23, D-124; https://{host}:8443 in v0.22, D-123; before that the literal https://icehack.asuscomm.com:8443).

• M2a owns the router and registers every route up front so that M3 and M4 only fill in handler bodies in their own files. The same for the utoipa ApiDoc. M2a creates the shell files of the later server milestones (D-004, §14.7) and the seams of §6.3 (D-015). server/rust-toolchain.toml pins the exact current stable Rust release and the Dockerfile uses the same version (§10.3).

• M2b writes the *State classes and repository interfaces of §14.2.4 so that M5 and M7 work against the same interfaces in parallel. It creates a module shell for every module of §6.2, with one empty entry composable per feature module (D-004), puts the feature convention of §6.2 (D-017) into the feature convention plugin, and fixes how resolveRange signals an invalid CUSTOM range (§14.5.4, D-018: IncompleteCustomRangeException, D-011). Its screenshot-test choice is D-010 (Roborazzi). It also created the Room 3 entities and KvittDatabase v1 in :data (D-012), so M5 builds on them.

• M5 owns :data and builds on the entities, KvittDatabase v1 and the exported schema android/data/schemas/se.hagstedt.kvitt.data.db.KvittDatabase/1.json that M2b created (D-012); it adds DAOs, the API client, sync and the repositories. Room 3 migrations take an SQLiteConnection (§14.2.3).

• M7x features use :core:fakes only; they never depend on :data. Each feature agent adds its fake scenarios in android/core/fakes/src/main/kotlin/se/hagstedt/kvitt/fakes/<feature>/ and nowhere else in that module. Each fills in its own module shell from M2b, follows the feature convention of §6.2 and takes shared UI from :core:design (D-019). All six landed on 2026-10-18 (1ea752c M7a, ea7d494 M7e, 7380e50 M7d, 0e1d99d M7b, 0b140aa M7c, c4ab35f M7f); their readings are D-069 to D-074 and D-080, the shared fixes they asked for went into M6b (b24c8b5, D-075 to D-079). M7g (landed 3dda414) did the feature-side cleanups after M6b.

• M6b (landed b24c8b5) is the :core:design fix pass after the M7 wave, in M6's paths (§14.7); see the §11.2 row.

• M12e (landed 8c60715 and b7b7483 on 2026-10-18, D-086 to D-095) took the contract requests that M5, M6, M7 and M8 had collected here, as one contract change on both sides (§14.8): the invite kind from pair() (D-086), the admin's name in invite links (D-087), SyncSummary.lastAttemptFailed (D-088), Rejection.actor (D-089), the device version name with server schema 3 (D-090), NewRecurringTemplate without an id (D-091), UpdateCheck (D-092), SettleState.untouched (D-093), the D-027 re-stamp in :data (D-094), and PushEvent in :core:model, the six screen-hosted snackbar hosts, snackbar resource ids from S-7 and S-8 and the launcher icon (D-095). The 128 px picture size was left unchanged by assumption: :data keeps fetching E-11 at 512 and no size parameter was added, since v1 does not need one (the owner confirmed on 2026-10-18 that it is not needed: single 512 size, §14.2.4). Room stays at schema 1 (the phone stores no devices). A phone running the M12e APK needs a server at schema 3 (§14.8 "Compatibility").

• Remaining contract requests (none is a contract change in v0.14; it needs the §14.8 rule when taken):

  • None open. S-22's "Licenser för öppen källkod" did nothing (no licences screen and no strings for one); the owner answered OQ-5 on 2026-10-18: no licences screen in v1, the row is removed (implemented by M8c, a0c25b0, D-099).

  The fid request was taken on 2026-10-18 (f56dcbe, D-096): the server sends the installation id in FCM HTTP v1 message.fid (§14.6).

• M2c-dev / M2c-pi (D-001, D-100): M2c-dev builds only what development needs on the Mac (landed); M2c-pi builds everything that concerns the Pi (registry trust, TLS through the owner's Nginx Proxy Manager since D-120, router, Pi deploy, APK publishing to the Pi, Drive upload, Gitea Actions) as the infra/pi/ bundle the owner runs, and runs last, after M8 and the phone test, before M10.

• M4 (landed 15056dc) added into_make_service_with_connect_info::<SocketAddr>() to serve so the per-IP rate limits of §8.6 see the peer address (D-032). Its tests are three binaries, tests/sync_api/, tests/push_fcm/ and tests/scheduler_daily/ (§14.7); the scheduler lives in src/tasks/scheduler.rs.

• M8 (landed cb832a7 and 3d9eea8, D-081 to D-085) is the only plan that edits :app after M2b. As built: both variants bind :data through di/AppDataModule.kt, which includes DataBindingsModule; the debug fakes module is deleted (D-081, revising D-041). The session gate shows S-1 for Unpaired and Unrecognised, S-2, and S-18 for Revoked (back on S-18 closes the app); Home shows S-3 while partner == null; each top-level screen draws its own bar (D-071). M6's :app requests are met: ProvideHousehold is implemented as LocalKvittHousehold, LocalKvittClock is provided from :data's Clock, and LocalAvatarPictures passes the User model to :data's Coil mapper. M5's requests are met: AppBuildInfo from BuildConfig; WorkManager with KvittWorkerFactory and the default initializer disabled; SyncTriggers.onAppStart on process start and onForeground on later returns; push handled by an expedited WorkManager job calling syncForPush (D-085); UpdateRepository.check on every start and resume, in release builds only (AC-16.5); Coil's singleton is :data's ImageLoader. The notification permission is asked after the first successful sync after pairing (AC-2.9). Network security configs per §8.5 (D-082); the merged release manifest exports only MainActivity and permission-guarded library receivers (§8.8); :app:assembleRelease builds unsigned when local.properties has no keystore keys (§10.6); FCM registration by Firebase Installation ID (D-083); invite links ignored while paired (D-084). The end-to-end test ran on 2026-10-18 on the owner's S26 against the development server: pairing with the bootstrap code OK; a scripted partner joined through a second admin device paired with kvitt-server pair-device (the CLI had no partner-invite subcommand then; kvitt-server invite-partner followed in 8660b7f, D-113); Home showed the account; an expense added offline showed the pending marker and synced after reconnect (pending 0, the server has the row); the owner's device registered fcm_token and app_version_name; a push by fid was delivered and the notification tap worked. M8b (landed 328c466) fixed what the owner saw: the invite-code field holds the raw code and draws the hyphens as a VisualTransformation with an exact offset mapping (cursor bug fixed, unit test InviteCodeFieldTest); the quick-row and grid selected badge is drawn above the ripple clip (it was cut off); KvittTopAppBar pads for the status-bar inset through a windowInsets parameter and KvittScaffold follows; chart bar corners top 4, bottom 2 dp (D-097); 221 goldens re-recorded. FcmMessageBody.fid in :data followed in 6eb3f85 (D-096). Still unverified on the phone: the status-bar fix (next install) and the design-spec §2.7 typeface check (the owner looked and had no complaint). Its contract requests were taken by M12e (D-086 to D-095); the fid field followed in f56dcbe (D-096). M8e (landed a59abeb, D-107) turned S-19's account, payer and split chips into EditorOptionRows; the unused AccountChip, PayerChip and SplitChip were removed in 1328afe. M8f (landed 956908a, D-108) made navigation instant (NavTransitions in :app).

• M10: the orchestrator relays every HUMAN step in chat. The keystore is created with the command of §10.6 at the repository root and referenced from android/local.properties (D-024, D-101).

• M2c-pi (D-100, revises D-023): no SSH from the Mac to the Pis and no allowances for agents on the Kvitt Pi, the Home Assistant Pi, Gitea or Google Drive. The agent writes and checks the infra/pi/ bundle on the Mac; the owner copies it to the Kvitt Pi, fills the .env placeholders (OQ-3) and runs the README checklist, answering yes/no per check. It runs as the last step before M10, after the app is proven on the phone. The bundle landed 2476667 on 2026-10-18 (D-103 to D-106: layout and scripts, image names and the Gitea workflow, the backup uid, the cert-sync and backup refinements); the NPM rework (D-120, 4f69ae0 to 9231a1d, 2026-10-19) replaced Caddy and cert-sync with a proxy host in the owner's Nginx Proxy Manager (§10.5); PLAN-M2c-pi.md carries a note that it is superseded there. D-125 (6e5981d, 2026-10-20) made the bundle a self-contained compose project in /home/jacobhagstedt/kvitt with no scripts and nothing outside that folder (§10.2, §10.10); the plan's note names it too. The remaining part is HUMAN, the owner installing the project on the Kvitt Pi (in progress 2026-10-20), and M10 depends on it.

• M9 (landed 50339ae) reuses the server's own push validation (kvitt_server::api::validate, rows) and the SqlAuditWriter, so imported rows pass the same checks as synced ones (§14.4.4). Its tests are one binary, crates/kvitt-import/tests/import.rs, over synthetic fixtures only; one test checks the §10.8 category table against data/splitwise_categories.csv.

• M12a, M12b, M12c (D-049 to D-054) carry the owner's UX-session decisions into the contracts and the landed code: M3, M5 and M9 were built with ten defaults, so this is a contract change against main, not only the spec. M12a (landed aa765bb) wrote contracts/, the checker and :domain's suggestCategory; M12b (landed 6eaccec) and M12c (landed b09f322) ran in parallel (disjoint paths, §14.7); their outcomes are D-055 to D-058. The Room schema stays at version 1: category rows reach the phone through sync. The colour hex values of slate and amber are not needed by M12 (:core:model holds token names only); they arrive with U2 and M6.

• M12d (D-059, landed 557af7e) added the two UI-contract members UX-9 found (ExpenseEditorOptions.frequentCategoryIds, CategoryRepository.deletable) to :core:model, :data and :core:fakes, in parallel with M6 (disjoint paths); its readings are D-060 to D-062 (§14.2.4 "Readings fixed in v0.10"). M7c and M7f consume them; the design spec's fallbacks (docs/ux/design-spec.md §3.7 and §6) are no longer needed.

• M6 (landed 7730a31) built :core:design with charts on Compose Canvas (D-063), the Material 3 Expressive fallbacks of D-064, the formatting tables of D-065 and the golden layout of D-066. Its contract requests for M8 (no change now): :app provides LocalAvatarPictures with an AvatarPictures that builds the authenticated E-11 Coil request from the user id and pictureVersion (§14.3.4); :app wraps every screen in ProvideHousehold(me, partner); :app provides LocalKvittClock (tests and previews pass a fixed clock); SyncSummary gains a "last attempt failed" field so SyncStatusPill can drop its failed parameter (§13.3 S-4); done by M12e: SyncSummary.lastAttemptFailed, and SyncStatusPill, syncPillVariant and syncLineText no longer take failed (D-088). The design-spec §2.7 open point (that FontFamily.Default keeps tabular figures and distinct weights 500/600/700 under every One UI font style on the S26) is checked at the M8 install on the owner's phone; on 2026-10-18 the owner looked and had no complaint (not checked under every One UI font style).

• M12f (landed dc7a296 to a0259ab, D-109 to D-112, D-116) took the Android findings of the AC-coverage audit and the security review (§11.4); see the §11.2 row. The S-1 confirm step for an unusual server (security review L-6) was not built: it needs a design state (OQ-6).

• Server gap pass (landed 8660b7f, D-113): kvitt-server invite-partner (§10.4), which closes the ops request of the M8 test; tests for invite-partner, migrate (schema at SCHEMA_VERSION, idempotent), healthcheck (200, 503, nothing listening) and the SIGTERM drain of serve; the push sender's push sent info line (§8.7); tools/contracts-check.py follows invite_kind (D-086), app_version_name (D-090) and fid (D-096), 134 checks pass.

• Server overhaul (landed 8103dae to b985ce9, D-114, D-115): shared stored-row reads and inserts (src/api/rows.rs, src/sync/rows.rs), shared invite creation and CLI plumbing, one test harness (tests/common/, §14.7), clippy pedantic wins, synchronous tasks::start (§6.3), not_implemented no longer produced (§14.3.2); the security fixes H-1 (D-115), M-3 and L-4 (D-114). Gate at landing: 268 server tests; all crates at their latest versions.

• Infra overhaul (landed 2fac1ec to e70fe0d, no decision): one Gradle lock helper tools/gradle-lock.sh for tools/gradle-serial.sh, tools/clean-builds.sh and infra/build-images.sh; the pre-commit hook runs the Android tests through tools/gradle-serial.sh with JDK 25 on PATH, JAVA_HOME untouched; install.sh keeps the deployed KVITT_TAG (moot since D-125: no install.sh); --provenance=false on buildx pushes and the workflow token through the environment (§10.3; reversed by D-120 point 7); RCLONE_REMOTE dropped from the development env (§10 intro). Infra security (landed 7fb86f5, D-117): Caddy log redaction and response headers (§8.7, §10.5.2), the non-root Caddy container (§8.9, §10.2), the development stack's single secret (§10 intro), the digest record (§10.3, §10.10; dropped by D-125 for docker image inspect), kvitt_cicd with write:package only (§10.3), the restricted cert-sync key (§10.5.1). D-120 carries the log redaction and the headers over to NPM's Custom Nginx Configuration (§10.5.2) and removes the Caddy container, the digest of its image and the cert-sync key.

• Overhaul outcomes (2026-10-18). Server: landed through b985ce9 (see the server overhaul above). Infra: landed through e70fe0d (see the infra overhaul above). Android overhaul (landed e4e6e5d to c582363, D-118, no prompt file, orchestrator brief): one screenshot and test harness in :core:design's test fixtures and the convention plugin kvitt.android.screenshots (§6.2); the shared failure texts, limits and savedSplitLabel in :core:design (§6.2); dead code removed (KvittMotion down to the seesaw spring, KvittIcon.Description, unused dimens and shapes, catalogue and fake samples); the catalog entries roborazzi-junit-rule, roborazzi-compose, androidx-hilt-navigation-compose and androidx-lifecycle-viewmodel-compose removed; one CopyCategoryKeywords task in build-logic shared by :data and :core:fakes (D-055 holds); one configureAndroidModule for the application and library plugins; S-7's state types in ExpenseEditorState.kt. Gate at landing: 941 tests, no golden changed; release APK 10.46 MB. Pushed to origin at c582363.

• M11 runs the import per §10.8 "Production run" (D-025). The rehearsal on 2026-10-18 ran both real files against a throwaway database and reconciled on both (Vardag 1746 rows, Hemma 37 rows); 21 rows were unmapped before D-044. The dry run of 2026-10-18 with M12b's mapping confirmed it: Vardag 1746 rows, 0 unmapped; Hemma 37 rows, 0 unmapped; both reconciled.

• W0 to W7 (D-134, §15.9): the web client programme. W0 and W7 run first in parallel (disjoint paths); W1 to W5 run in parallel once W0 has landed; W4's W-11 and W6 wait for W7. W0 owns web/** except the feature folders, registers every route with a placeholder page per feature folder (as M2a registered every route, D-004), and lists its module paths in its report; W1 to W5 build only inside their feature folders and take everything shared from W0's modules (a missing shared piece is a request to the orchestrator, as M7x's requests went to M6b). A second agent to land that changed web/package.json resolves web/package-lock.json with npm install on rebase (as Cargo.lock, §14.7). A plan that changes contracts/openapi.yaml regenerates web/src/api/schema.d.ts (§15.3). Web agents do not use the phone or tools/gradle-serial.sh; a manual check runs against a throwaway server, never the owner's development or Pi data (§15.4). The orchestrator adds the web gate to CLAUDE.md "Build and verify" (D-131). W1 to W5 landed 2026-10-21 (934eee7, a65ab71, f9a9bfb, 1aecf51, 3ebe57d; D-144 to D-154, D-150 unused) with the web gate green on main (59 test files, 532 tests at 1aecf51); a web fix (83f5293) followed (598 tests). Pieces built twice or three times in feature folders and other loose ends are listed for a W0b plan in docs/HANDOFF.md "Web follow-ups". W0b landed 5305f37 (v0.34). All of W0 to W7 are landed and verified: v1.0.3 (built on the Mac from 8fa9198, D-211) runs on the Kvitt Pi and the owner checked the web client and the phone's Insights against it on 2026-10-24 (§11.4).

• K0 to K3 (D-176, §11.1): the card-purchase programme. K0 runs first, on the Mac only, with the owner (a local test app for fast feedback before any Android work, owner's refinement 2026-10-24; the app landed 2ce317f); K0 is done (run 2026-10-24, report docs/spikes/K0-enable-banking.md) and its answers are in SPEC v0.36 (D-177 to D-180), so K1 to K3 can start. The reports of K1 to K3 propose spec text and decisions that a docs agent records: K1's in SPEC v0.38 (landed 671c00d, D-181 to D-188), K2's in v0.39 (landed a8f91ee, D-191 to D-200), K3's in v0.40 (landed faeb752, D-201 to D-207) (decisions from D-191 to D-210, disjoint ranges per plan). Then K1, K2 and K3 run in parallel in their own worktrees (disjoint paths, §14.7): K1 owns the contract (contracts/**, the migration text, the vectors) and lands first; K2 and K3 build against the spec and fakes, and rebase on K1 before their gates (K2's DTO tests and K3's generated types need K1's contract); K3 lands after K2, whose docs/ux/strings.csv rows it imports (npm run i18n:import). K2 uses the phone only when its brief names it; K1 and K3 never use the phone. No plan connects to the owner's real card except through the owner's own BankID step; no plan stores, prints or commits a real purchase.

11.4 Validation reports

Reports in docs/validation/ are deliverables (CLAUDE.md); they carry aggregates only and record the commit they were taken at. The release reports first-release.md and restore-drill.md (M10, AC-18.2) are still to be written.

• docs/validation/ac-coverage.md, the AC-coverage audit taken at 956908a (ed1b130 before the history rewrite; SPEC v0.16), read-only: 270 rows, 260 Done, 5 Partial, 1 Missing, 4 not verifiable without a device. Verdict: feature complete in code; not yet complete against §4's acceptance rule. Its two mismatches in shipped behaviour are fixed by M12f: S-16 opens the lost change read-only (D-109) and S-22 reads the server version from /health (D-110); M12f also added tests for the §9.2 effect cases, AC-2.9, the 429 retry, D-040 refusals and WorkManager unique work. Still open: the AC-18.2 restore drill (Missing), AC-20.1 observed on the Pi (M10), and a KvittWorkerFactory test. Observed 2026-10-24 (D-156): AC-18.1, the first backup on the Pi with its snapshot pair in the Drive folder (verified by the owner); AC-16.3, the real PackageInstaller install on both phones (release 140), once Samsung Auto Blocker was off; the editor keyboard fix (S-19, S-15, S-6, 05ec3f3) on the device. Observed 2026-10-24 (D-211), the web client's first use (FR-21) and W6: image v1.0.3 on the Kvitt Pi, server and backup healthy; https://kvitt.suorra.duckdns.org/app/ paired from the laptop browser with a device invite; the owner reports "All seems to work" for Home and an account, add, edit and delete of an expense, the CSV export, recording and deleting a payment, analytics with a category drill-down and Insights, every settings page, revoking the browser from the phone, and the Android Insights section on S-11 against this server.
• docs/validation/security-review.md, the security review taken at 18c527f (SPEC v0.17), read-only: Critical 0, High 1, Medium 3, Low 10, Info 8; the design matches §8 and is sound. Status at v0.18: L-6 kept as built and L-7 fixed (D-116); L-1, L-2, L-5, L-9 and M-2 fixed in infra (D-117); L-8 fixed (e70fe0d); H-1 (the in-memory rate limiter, 725901c), M-3 (picture decoding memory, baa5806) and L-4 (fcm_token length, b985ce9) were fixed by the server overhaul (D-114, D-115); L-10 (a member gets forbidden rather than not_found for another user's device): owner answer 2026-10-24, not_found (D-156), fixed in 07c36d2 (E-16). Owner answers of 2026-10-19: M-1 (backup encryption) no, closed as an accepted risk (§8.1, §8.7); L-3 (APK download rate) accepted and fixed (96e4cbd, D-119: 10 per minute per IP for E-6); the 16 megapixel picture cap and the 512-character fcm_token limit (D-114) confirmed. H-1 had to be fixed before the server was opened to the internet (fixed, 725901c). D-120 (2026-10-19): L-1's redaction and D-117's headers now live in NPM's Custom Nginx Configuration (§10.5.2); L-2 and M-2 are moot (no Caddy container, no Home Assistant SSH key); the L-8 fix is reversed (the token is interpolated in the run line again, masked by act_runner, §10.3); I-5's check is the conntrack check of §10.10. The review carries dated notes under those findings.

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12. Open questions

Only things that cannot be decided without the owner. Everything else in this spec is decided.

Id	Question	Needed by	Default if unanswered
OQ-1	Answered (D-001): the registry is a Gitea instance on another Pi at http://gitea.lan, plain HTTP, reachable only on the home Wi-Fi; images are built by Gitea Actions from the owner's example workflow (provided; .gitea/workflows/build-images.yaml, D-104).	M2c-pi	answered
OQ-2	Answered (D-003): two exports, English and Swedish header variants, member columns in either order, ISO dates, point decimal, double-quoted fields, trailing empty line and Total balance / Totalsumma row, payment category Payment / Betalning, all rows SEK. Group "hemma" becomes account "Hemma", the general group becomes account "Vardag". Details §10.8 and PLAN-M9.	M9, M11	answered
OQ-3	Answered by placeholders (D-100, revised by D-120): the LAN address of the Kvitt Pi (<kvitt-pi-address>; its .env key KVITT_PI_HOST was dropped in 200c99f) and the LAN IPv4 address of the Home Assistant Pi, where NPM runs (HA_HOST); with D-120 also the Kvitt host name (KVITT_PUBLIC_HOST, owner-chosen, recorded in HANDOFF). SSH port and user of the Home Assistant Pi; the directory holding fullchain.pem and privkey.pem there; which SSH add-on is used (cert-sync removed by D-120). The owner fills HA_HOST in the Pi's .env (D-125) and uses the Kvitt Pi's address in NPM and in scp; no agent needs them.	M2c-pi	answered
OQ-4	Answered: the Google Drive backup folder id is 1jDp1dGE5R3H2DBcXCqIPN1iWzQnPkdlV (§10.9).	M2c-pi	answered
OQ-5	Answered 2026-10-18 and implemented (D-099, a0c25b0): no licences screen in v1; S-22 has no "Licenser för öppen källkod" row.	M10	answered
OQ-6	Answered 2026-10-24 (D-156): no confirmation step on S-1 for an invite link that prefills a server other than the release default (RELEASE_SERVER_URL, AC-2.6) (security review L-6); the default stands: S-1 opens its server row expanded for a non-default server so the address is visible (AC-2.6, D-116).	M10	answered
OQ-7	Should a new card purchase raise a notification on the holder's phone (a local one, built from the holder's own data; never an FCM payload with content)?	K2	Not in this version: purchases appear on the next sync without a notification (D-171)
OQ-8	Should several purchases be turned into expenses at once ("Lägg till i konto…", one expense each with the account's default split)?	after K2	Not in this version (D-171); one purchase at a time through S-7
OQ-9	CardPurchase.linked (§14.2.4) is null both when a purchase is unlinked and while its linked expense is not yet on the phone (for example a link made in the web client to an expense the phone has not pulled yet), so the purchase is listed under "Kopplade" without its "Kopplad till" line and its sheet briefly offers "Skapa utgift" and the matches. Add linkedExpenseId to CardPurchase so the sheet can say "Kopplad" without the expense's details (a UI-contract change, §14.8)?	next Android card pass	Not now: the window lasts until the next household sync brings the expense

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13. UX sprint

A brief for one UX agent (Opus) who has read this spec and nothing else. It runs right after M0, in parallel with M1, and before any UI work (M6, M7). It produces proposals; the owner chooses; the UX agent then writes the binding design spec. The UX agent writes no Kotlin.

13.1 Context the UX agent must design for

• Two adults in Sweden, one household, using Samsung Galaxy S26 (about 411 × 891 dp viewport, 6.3") and S26+ (about 411 × 891 dp at a higher density, 6.7"). Portrait only. Android 16, One UI on top; the app uses Material 3 (Expressive where stable) and must not imitate One UI.
• Most sessions are 10 seconds: add an expense right after paying. The add flow is the most important flow; it must need at most: open app, tap add, type amount, type description, tap save (category and account defaulted, AC-8.6).
• The second most important view is "who owes whom" on Home.
• Swedish is the primary language (both users' phones are Swedish), English must fit too. Swedish words are long ("Utgiftskonto", "Återkommande"); designs must survive them at 200 % font scale.
• Light and dark theme follow the system. Dynamic colour (Material You wallpaper colours) is offered as an option per direction only if the direction still works with it; the default is the direction's own palette.
• Money must be legible at a glance: amounts in tabular figures, direction ("owes you", "you owe") always in words plus colour, never colour alone.
• Accessibility: touch targets ≥ 48 dp, contrast ≥ 4.5:1 for text, TalkBack labels for every icon-only control, nothing conveyed by colour only, layouts that reflow at 200 % font scale.
• Category icons are Material Symbols from the set in §9.7; category colours are the tokens of §9.7 (the UX agent may change hex values, not token names, and must give light and dark values with contrast checked against both surfaces).
• Users are shown by avatar (picture or initials, AC-4.5) and display name. The viewer is always "you" / "du".

13.2 Navigation model (binding, D-048)

• Destination changes are instant, with no transition animation (D-108); motion stays inside screens (design-spec §2.11).
• Bottom navigation with three destinations: Home (Översikt), Analytics (Statistik), Settings (Inställningar). Revised by D-172 (owner, 2026-10-24): bottom navigation with four destinations, in this order: Home (Översikt), Card purchases (Kortköp, S-23), Analytics (Statistik), Settings (Inställningar). Kortköp sits next to Översikt because turning purchases into expenses is daily work beside the add flow, while Statistik is visited now and then and Inställningar stays last. Both users always see the tab; without a connection it shows its empty state with "Anslut kort". An "Aktivitet" feed (the other person's changes across accounts) was considered as a fourth destination and not taken for v1 (D-048).
• A floating action button "Add expense" (Lägg till utgift) on Home and on Account detail.
• Account detail, expense editor, expense detail, settle up, settlement detail and all settings sub-screens are pushed screens with a top app bar and back.
• The expense editor is a full-screen screen, not a bottom sheet (the numeric keyboard needs the room).
• Wiring (D-071, as built by M7a to M7f and connected by M8): the top-level screens S-3, S-4, S-11 and S-13 render their own KvittNavigationBar and take onNavigate: (KvittDestination) -> Unit; the :app scaffold draws no second bar, and the NavHost switches top-level destinations from those lambdas. Since D-172 S-23 is the fourth top-level screen that draws the bar, and KvittDestination (:core:design) gains Cards between Home and Analytics (as built by K2, a8f91ee: enum class KvittDestination { Home, Cards, Analytics, Settings }, icon credit_card, label nav_cards; a label that does not fit its slot at a large font scale shrinks to fit, down to 70 %, D-197). Navigation-argument keys are constants in each feature (ARG_EXPENSE_ID and ARG_ACCOUNT_ID; SettleArgs.SETTLEMENT_ID and SettleArgs.ACCOUNT_ID; DrillDownArgs.KEYS; settings "categoryId" and "templateId"), read through SavedStateHandle.
• Result snackbars (D-071): the result of S-7 ("Utgiften sparades"), of S-9 and of archiving an account is shown by the screen returned to; the account-archived snackbar has an undo action (common_undo, "Ångra"). As built by M12e (D-095): six screens host :app's shared snackbarHostState in their own scaffold (Home, AccountDetail, ExpenseDetail, SettlementDetail, DrillDown, SyncStatus), so a snackbar never overlaps a FAB or the bottom bar; :app has no overlay host. Features hand :app string resource ids, never resolved strings: ExpenseEditorScreen.onSaved(ExpenseId, @StringRes Int?), and onDeleted() on S-7 and S-8 takes no argument, :app then shows snackbar_expense_deleted.
• Session gate (as built by M8): S-1 for an unpaired or unrecognised session, S-2 for the profile step after a partner pairing only (AC-2.10, D-086; a member pairing a second phone with a device invite goes to Home), S-18 for a revoked device (back on S-18 closes the app). Home shows S-3 while the household has no partner (partner == null).

13.3 Screens and what each must show

Each screen must be designed in these states where they apply: loaded, empty, offline (with pending changes), loading (first sync only; afterwards data is local), error (a failed online action), and, for lists, long content (long Swedish names, 7-digit amounts). Which states apply to which screen is listed per screen in U2's docs/ux/design-spec.md; that list is the binding one for U2's gate and for the feature milestones' screenshot tests.

Id	Screen	Must show	Actions
S-1	Pairing	App name and one-line purpose; server URL field (prefilled; in release builds with RELEASE_SERVER_URL, which :feature:onboarding receives through the Hilt qualifier @ReleaseServerUrl for the prefill and for the non-default-server check of AC-2.6, D-121); invite code field (12 characters, shown in groups of 4); display name field ("Ditt namn", 1 to 40 code points, §9.6), required on a first pairing and hidden in the "Para ihop telefonen igen" variant (D-050); explanation of where the code comes from (onboarding_code_help with the admin's name when the invite link carries from, else the generic help line onboarding_code_help_generic; PairingScreen(initialAdminName) and PairingViewModel.prefill carry the name from :app's AppLink.Invite, and a pasted link fills it too, D-087); progress while pairing; errors invite_invalid, network error, rate_limited	Pair; paste code
S-2	Partner profile step	Display name field (prefilled; a blank name shows onboarding_error_name_required "Skriv ditt namn"), avatar with "Add picture"; the owner's name and avatar ("You are joining Jacob"). Shown only after a partner pairing (Pairing.inviteKind, D-086)	Continue
S-3	Waiting for partner	Explanation that the partner must join first; the pending invite's expiry if any; error state when fetching the invite failed (snackbar with "Försök igen")	Invite partner (goes to S-21); Settings
S-4	Home	Global balance header: both avatars, wording per §9.3, amount; "Settle up" button when non-zero; sync line: "Last synced …" and pending count when > 0, tap opens S-16 ("Sync failed" when SyncSummary.lastAttemptFailed; SyncStatusPill takes no failed parameter, D-088); update banner (S-17) when available ("Later" hides it for the ViewModel's lifetime only, so it returns on the next start); list of active accounts, each with name, balance wording and amount, number of expenses this month; collapsed "Archived (n)" section; empty state when no accounts ("Create your first account")	Add expense (FAB); Settle up; open account; New account; Pull to refresh (sync now, D-127)
S-5	Account detail	Account name, default split with names (ratios written "60/40", common_ratio), balance header; list of expenses and settlements interleaved by date, grouped by month with month totals (household spend; month headers are not sticky), each expense row per AC-8.10, each settlement row per AC-11.7 (its title may wrap to 2 lines, 3 at 200 % font scale, and its second line is the type label ledger_settlement_label "Betalning" from :core:design, D-068); archived badge if archived (an archived account hides the add-expense FAB, AC-6.4, and keeps "Settle this account", D-052); pending-sync marker per row	Add expense (not on an archived account); Settle this account; Edit account; Archive / Unarchive; Delete (only if allowed); Pull to refresh (sync now, D-127); "Från kortköp" (overflow menu, first item, only while the viewer has a card connection and not on an archived account, D-199; opens S-27, AC-22.9)
S-6	Account editor	Name field; default split control (one slider or stepper plus two percent fields that always sum to 100, two decimals allowed); preview "Of 100,00 kr: Jacob 60,00 kr, Anna 40,00 kr"; "Needs connection" state; the discard dialog has a title and no body text (D-080)	Save; Cancel
S-7	Expense editor	Amount entry (large, numeric keyboard, kr); description; account picker (active accounts); category picker (grid of icon + colour + name, active categories; for a new expense the category is selected from the description per §9.11, with no marker); date (today default, date picker); payer toggle (two avatars: "Paid by"); account, date, payer and split shown as four fixed full-width rows in that order, which do not move when a value changes (D-102); split section: mode chooser (default "Account default 60/40", ratio "Custom ratio", exact "Exact amounts", full "All on one person") and its controls; live preview of each person's share; notes (collapsed by default); validation errors inline; delete in edit mode; opened from a card purchase (S-23's sheet or S-27, CP-9, D-169) it starts as a new expense prefilled from the purchase, and "Spara" also links the purchase (a foreign-currency purchase leaves the amount empty); after saving, the snackbar "Utgiften sparades" without "Ångra" (an undo would be an audited create and delete that also notifies the partner, D-052), shown by the screen returned to (D-071), onSaved handing :app the string resource id (D-095); the quick row is filled by quickRowCategories (D-075) and category labels take up to two centred lines, a longer custom name ending the second line in "…" (D-076); the discard dialog has no body text (D-080)	Save; Cancel; Delete (edit mode)
S-8	Expense detail	Amount, description, category, account, date, payer, each user's share and the split mode, notes, "Recurring: " when generated; for the card holder only, when a purchase of theirs is linked to it, the line "Från kortköp: , " (expense_detail_from_card) with "Ta bort koppling" (AC-22.10, D-169); timeline (AC-12.4, AC-12.5); "deleted" state when opened from a notification of a deletion; "missing" state (not yet on this phone) with "Synka nu" (expense_detail_sync_now), online only (§9.9, D-080); after a delete :app shows snackbar_expense_deleted on the screen returned to (D-095) Edit; Delete S-9 Settle up Direction ("Anna pays Jacob" with a swap control); amount; allocation list: account name, account debt, editable allocated amount, over-settle warning per row (AC-11.5); remaining-to-allocate indicator; "Add account"; date; note; per-account variant with a single fixed row, which keeps the direction swap (§9.4: per-account settle-ups go either way) and an editable amount (AC-11.4 "defaults to") (D-052); when editing, the saved rows count as edited and "Föreslå igen" re-proposes; the info line on untouched accounts reads SettleState.untouched (nets without the settlement being edited, empty for a per-account settle-up, D-093, revising D-074's reading of Home balances); the discard dialog has no body text (D-080) Confirm; Cancel S-10 Settlement detail Payer, recipient, amount, date, note, allocations per account; timeline; "missing" state with "Synka nu" (settle_detail_sync_now), online only (§9.9, D-080) Edit; Delete S-11 Analytics Range selector (presets of AC-14.2 plus custom); granularity toggle month/week; measure toggle household / my share; group-by toggle category/account; total for range; chart 1 stacked bars over time with legend; chart 2 category breakdown; chart 3 account breakdown; empty state ("No expenses in this period"); a chart whose range has no expenses shows only the 0 baseline, with no gridline values (D-068). Total card (D-069): caption " · Hushållet" for the household measure and " · N veckor" in week granularity; for my share the label is "Totalt · Min del" so the caption does not repeat it; month presets show whole-month ranges ("maj–okt 2026"), custom ranges and week granularity show days (§9.8, D-077). Legend and stacking order: categories by sortOrder, accounts in AccountRepository.all() order (AnalyticsState.groups order is unspecified, §14.2.4). Loading means SyncSummary.lastSuccessAt == null and shows skeleton cards; offline looks like loaded; no error state (analytics are local, AC-14.1). Insights section (D-142, D-143), online only. Change filters; tap a bar or a row to open S-12; pick a category in Insights; "Försök igen" S-12 Analytics drill-down Title naming the filter ("Mat & hushåll, oktober 2026"; a week as in docs/ux/strings.csv, "Vardag, vecka 41"; a category or account over the whole range ", ") (D-070); total; expense rows as in S-5. A category or account over the range adds, above the total, its own range selector (AC-14.2 presets plus custom) and month/week toggle, both starting from S-11's values and changing S-12 only; below the total, the line chart of AC-14.11; then the rows. A range with no expenses reads "No expenses in this period" (D-128). No loading and no error state (D-070) Open expense; change range or granularity S-13 Settings hub Own avatar and name; partner's avatar and name; rows: Profile, Categories, Recurring expenses, Anslut kort ("Connect card", fourth row of the first group, subtitle "Ansluten · giltig till ", "Har upphört" for an expired connection (D-199) or "Läs in dina kortköp", D-172), Devices, Invite partner or Pair a device (admin), Sync status, About Navigate S-14 Profile Avatar with change/remove; display name; "Needs connection" state Save S-15 Categories List: icon, colour, name, archived section; editor: name (with "Reset name" for defaults), icon grid (33 icons of §9.7), colour swatches (14 tokens); delete or archive with the reason when delete is not allowed Add; Edit; Reorder (drag); Archive; Delete S-16 Sync status Last successful sync time; pending changes count with a list (the shared ledger rows of :core:design, D-019, not a separate 36 dp row); "Changes not synced" list from sync_rejections with what was lost and why (copy per §14.4.6 reasons); clock-skew warning; "Sync failed" when online and SyncSummary.lastAttemptFailed (D-088); the stale-change copy names Rejection.actor, the partner when it is null (D-089); "Sync now", online only (§9.9, D-080); "Öppna" on a rejection shows the phone's lost version read-only (D-109): a dialog "Din version" (home_sync_lost_title, body home_sync_lost_body) with the ledger row it would have been (read-only: the row's onClick is null), the account, payer, split and notes (Rejection.lost, §14.2.4), the badge "Du tog bort den här" (home_sync_lost_deleted) when the refused change was a deletion, and "Visa nuvarande version" (home_sync_lost_show_current), which opens S-8 or S-10; when lost is null (unreadable payload, or its category or a user is not on the phone) "Öppna" opens the current version directly Sync now; open a rejected change (read-only); dismiss it S-17 Update available Banner on Home with version name; dialog explaining "Install unknown apps" the first time; download progress; failure (download, or the install refused or failed with its reason, AC-16.7, D-155) Update; Later S-18 Device removed Explanation that this phone's access was removed and local data deleted Pair again (goes to S-1) S-19 Recurring expenses List: description, amount, account, "Every month on day 25", next date, paused badge; editor with the expense fields of S-7 (no date); account, payer and split as three fixed full-width rows (Konto, Betalt av, Delning; D-102, D-107) plus day of month (a new template defaults to today's day, AC-9.8, D-072), first month, optional last month, pause switch; a new template is sent as NewRecurringTemplate (RecurringForm.newTemplate()), an edit as RecurringTemplate (RecurringForm.template(original, …)), D-091; the discard dialog has no body text (D-080) Add; Edit; Pause/Resume; Delete S-20 Devices Rows per AC-3.1; the app version shows Device.appVersionName ("Kvitt 1.1"), else the version code (D-090) Revoke (with confirmation) S-21 Invites For the admin: "Invite partner" (only before the partner joins) and "Pair another device" for either user; a created invite shows the code in groups of 4, the link, expiry, and a share action (Android share sheet); list of pending invites with cancel Create; Share; Cancel S-22 About App version name and code, server URL (the paired server; before pairing the build's release server, AppBuildInfo.releaseServerUrl, D-122), server version from E-1 /health, fetched when S-22 opens while online, shown as " (schema )" (settings_about_server_version_schema, "1.1.0 (schema 3)"); offline or when the call fails, the X-Kvitt-Server-Version header of the last response without the schema (AboutState, §14.2.4, D-110); no open-source licences row (OQ-5, D-099); after "Check for update": UpdateCheck.UpToDate shows "Du har den senaste versionen" (settings_about_up_to_date), UpdateCheck.Failed shows "Kunde inte nå servern" (common_could_not_reach_server) (AC-16.6, D-092); the button calls UpdateRepository.checkNow(), which always asks the server (D-140) Check for update S-23 Card purchases (Kortköp; :feature:cards, top-level, D-172) Top app bar "Kortköp"; a header card with the card's artwork (small, CardArt), its name, "Bara du ser dina kortköp" and "Uppdaterad " (§9.8 relative form) with an "Uppdatera" button (a spinner and "Uppdaterar…" while E-42 runs); filter chips "Att hantera" (default), "Kopplade", "Ignorerade", "Alla", each with its count; the purchases of the filter, newest first, grouped by day (day headers in the §9.8 list form), each row: merchant (one line, ellipsis), amount (MoneyText, or " " with "Utländsk valuta"), "Preliminär" chip when pending, "Insättning" for a credit (only under "Alla"), and under "Att hantera" the match chip of CP-10 ("Koppla till " or " möjliga utgifter"); under "Kopplade" the line "Kopplad till · ". States: no connection (empty: large artwork, "Anslut ditt kort", "Se dina köp här och gör om dem till utgifter med några tryck. Bara du ser dem.", "Anslut kort" → S-24); first fetch ("Hämtar dina köp…" with a progress indicator, while connected and no fetch has finished); loaded; empty filter ("Inget att hantera" / "Nya kortköp visas här." for "Att hantera", "Inga köp här" for the others); offline (the stored list, "Uppdatera" disabled with "Kräver anslutning"; linking and ignoring still work, CP-9); expiring (warning banner "Kortanslutningen upphör " with "Förnya med BankID", CP-6); expired (banner "Kortanslutningen har upphört" with "Förnya med BankID"; list kept); fetch failed (banner "Kunde inte hämta köp. Senast uppdaterad " with "Försök igen", CP-14); long content (long merchant texts, 7-digit amounts). Purchase sheet (bottom sheet on tapping a row): merchant, the purchase date in the detail form, amount, status ("Preliminär" / "Bokförd"); for a debit purchase to handle: "Skapa utgift" (primary) → S-7 prefilled (CP-9); "Koppla till befintlig utgift" with up to 3 matches (each: description, account, payer, date, amount; one tap links and closes the sheet with the snackbar "Kopplad" and "Ångra"), or "Ingen utgift med samma belopp runt det här datumet"; "Välj en annan utgift" (the CP-10 list in a second sheet); "Ignorera" (snackbar "Ignorerad" with "Ångra"). Linked: "Öppna utgift" (S-8), "Ta bort koppling". Ignored: "Sluta ignorera". Credit: the note "Insättningar och återbetalningar är inga utgifter. Ändra den ursprungliga utgiften för hand vid behov." and no action. Foreign currency: the note "Beloppet är i : skriv beloppet i kronor." above "Skapa utgift". As built by K2 (a8f91ee, design-spec S-23): at most one banner, above the header card, expired before expiring before fetch failed; expired also disables "Uppdatera"; the header card opens S-26 (TalkBack click label "Kortanslutning", cards_connection_settings); during the first fetch the header has no "Uppdaterad" line and no filters show; the four filter chips wrap to a second row (D-198); a row shows "Utländsk valuta" as a badge next to "Preliminär" or "Insättning"; the one-match chip links in one tap (snackbar "Kopplad" with "Ångra"), the " möjliga utgifter" chip opens the sheet; back from "Välj en annan utgift" returns to the purchase sheet; a failed "Uppdatera" on the network shows the snackbar "Kunde inte nå servern"; a purchase linked to an expense not yet on the phone is listed under "Kopplade" without the "Kopplad till" line and its sheet shows the to-handle actions until the expense arrives (CardPurchase.linked is null then, OQ-9) Uppdatera; Pull to refresh; filter; open a purchase; Skapa utgift; link a match (also from the row's chip); Välj en annan utgift; Ignorera / Sluta ignorera; Ta bort koppling; Öppna utgift; Förnya med BankID; Anslut kort S-24 Connect card (Anslut kort; :feature:cards, pushed from S-13, D-172) App bar "Anslut kort"; intro "Välj ditt kort. Kvitt läser dina köp men kan aldrig betala eller flytta pengar."; one large tile per catalogue entry (E-36): the card's artwork (CardArt, full width, card aspect ratio 1.586:1, corner radius 16), name, issuer; a connected card's tile adds "Ansluten · giltig till " and opens S-26; a provider not available shows "Inte konfigurerat på servern" and is disabled (AC-22.1); loading (skeleton tile), offline ("Kräver anslutning", tiles disabled; the catalogue comes from the server), error ("Kunde inte nå servern" with "Försök igen"). As built by K2: offline shows the NeedsConnectionBanner "Listan över kort hämtas från servern. Anslut telefonen till internet." (cards_connect_offline_body, D-200) and the cached catalogue entry's tile disabled (D-194); E-36 is asked again when the phone comes online; the connected line's date is in the §9.8 list form Open a card (S-25 or S-26) S-25 Connect a card (:feature:cards, pushed from S-24, or from "Förnya med BankID") App bar with the card's name; the artwork (large); "Hämta köp från de senaste" with a segmented choice wrapping filter chips (D-198) "7 dagar", "30 dagar" (default), "90 dagar", "180 dagar" (CP-3); the note "Du kan korta perioden senare. En längre period kräver BankID igen."; the button "Anslut med BankID" (renewal: "Förnya med BankID", the history preset to the connection's). After the tap: waiting state "Väntar på BankID…" with "Slutför i webbläsaren och i BankID och kom sedan tillbaka hit." and "Avbryt" (stops polling; the attempt expires by itself); connected: "Kortet är anslutet" then S-23; failed: "Det gick inte att ansluta kortet" with "Försök igen"; timed out: "Anslutningsförsöket tog för lång tid" with "Försök igen"; offline: the button disabled with "Kräver anslutning". As built by K2: E-38 is polled every 2 s only while S-25 is open and resumed (the Custom Tab on top pauses it) and once at once when the return link arrives (D-196); "Kortet är anslutet" shows for 1.5 s, then S-23; "Avbryt" returns to the choice; E-37 failing on the network shows "Kunde inte nå servern" above the button, any other failure, or no browser to open the bank page, the failed state; timed out is shown when E-38 answers expired (the server's 15 minutes), with no clock check on the phone Anslut med BankID; Avbryt; Försök igen S-26 Card connection (:feature:cards, pushed from S-24, or from S-23's header) App bar with the card's name; artwork; status line ("Ansluten", "Har upphört"); "Giltig till " (detail form); "Senast uppdaterad "; "Historik vid anslutning" with the current value, shorter values selectable (E-41), a longer one only through "Förnya med BankID" with the note "En längre period kräver BankID igen" (CP-3); "Förnya med BankID" (always offered; highlighted from 14 days before valid_until, and when expired: filled instead of tonal); "Koppla från" (error colour) → dialog "Koppla från ?" / "Köp som du inte har kopplat eller ignorerat raderas. Utgifter du har skapat finns kvar." with the checkbox "Radera även kopplade och ignorerade köp" and "Koppla från" / "Avbryt" (CP-12); offline: every action disabled with "Kräver anslutning". As built by K2: artwork, then a facts card (status line with a filled check_circle in owed or a filled error in error, "Giltig till", "Senast uppdaterad"), then the history as wrapping chips listing only the current value and shorter ones (D-198), then the two buttons; a network failure shows the snackbar "Kunde inte nå servern"; after "Koppla från" the screen closes Change history; Förnya med BankID; Koppla från S-27 From card purchases (Från kortköp; :feature:cards, pushed from S-5) App bar "Från kortköp" with the account's name as subtitle; the viewer's purchases to handle (debit, SEK or foreign, neither linked nor ignored), newest first, as S-23's rows without chips, grouped by day under S-23's day headers (as built by K2); empty: "Inga kortköp att hantera"; works offline; S-7's "Utgiften sparades" shows here on return Tap a purchase: S-7 prefilled with this account (CP-9) System notifications (copy needed in both languages, built per AC-13.5): Type Title Body expense_created " added an expense" " · · " expense_updated " changed an expense" " · " expense_deleted " deleted an expense" " · " settlement_created " recorded a payment" " paid " settlement_updated " changed a payment" " paid " settlement_deleted " deleted a payment" "" recurring_expense_created "Recurring expense added" " · · " sync_batch " made changes" "Open Kvitt to see them" any, when the sync failed " changed something in Kvitt" (or "Kvitt" without actor name) "Open Kvitt to see it" The UX agent writes the Swedish versions. Invite landing page (E-4, AC-2.5). Server-rendered HTML, so these strings live in the server (M3's src/api/landing.rs), not in the app's resources: Element English Swedish App name Kvitt Kvitt Download button Download Kvitt Ladda ner Kvitt Open button Open in Kvitt Öppna i Kvitt Instruction sentence Install Kvitt, then open this link again on your phone. Installera Kvitt och öppna sedan den här länken igen på din telefon. The download button is omitted while no APK is published; the 404 page shows only "Kvitt" and "404" (AC-2.5). Card callback page (E-39, CP-2). Server-rendered HTML in the language of Accept-Language (Swedish when it prefers sv, English otherwise), so these strings live in the server (K1's src/cards/callback.rs), not in the app's resources. It shows the app name, one heading, one sentence and one link; no amount, merchant, card name or any other personal data: Element English Swedish App name Kvitt Kvitt Heading, success Card connected Kortet är anslutet Sentence, success Your card purchases are being fetched. Go back to Kvitt to see them. Dina kortköp hämtas nu. Gå tillbaka till Kvitt för att se dem. Heading, failure The card could not be connected Det gick inte att ansluta kortet Sentence, failure Go back to Kvitt and try again. Gå tillbaka till Kvitt och försök igen. Link Back to Kvitt Tillbaka till Kvitt The link is kvitt://cards/connected?attempt=<attempt id> for an attempt started by the app and /app/cards?attempt=<attempt id> for one started by the web client; for an unknown, used or expired state the failure page has no link (the user closes the tab; the client's own screen shows the failure or the timeout from E-38). The page is sent with Cache-Control: no-store and Referrer-Policy: no-referrer; the attempt id is not a secret (it only names the attempt to its own user's devices, E-38). Card purchase strings (K2 adds them to docs/ux/strings.csv with these keys; the web uses the same keys, §15.3). Keys of :feature:cards start with cards_; nav_cards is :core:design's, settings_cards* :feature:settings's, account_from_card_purchases :feature:account's, expense_detail_from_card and expense_detail_unlink_card :feature:expense's (§6.2, D-017). Existing keys are reused where the text is the same (common_needs_connection, common_retry, common_undo, common_cancel, common_could_not_reach_server, the §9.8 relative times). Plurals as key:one / key:other. TalkBack labels and any key not listed are K2's, recorded in its report. Key English Swedish nav_cards Card purchases Kortköp settings_cards Connect card Anslut kort settings_cards_connected Connected · valid until %1$s Ansluten · giltig till %1$s settings_cards_none Read your card purchases Läs in dina kortköp account_from_card_purchases From card purchases Från kortköp expense_detail_from_card From card purchase: %1$s, %2$s Från kortköp: %1$s, %2$s expense_detail_unlink_card Remove link Ta bort koppling cards_title Card purchases Kortköp cards_private_note Only you see your card purchases Bara du ser dina kortköp cards_updated Updated %1$s Uppdaterad %1$s cards_refresh Refresh Uppdatera cards_refreshing Refreshing… Uppdaterar… cards_filter_to_handle To handle Att hantera cards_filter_linked Linked Kopplade cards_filter_ignored Ignored Ignorerade cards_filter_all All Alla cards_pending Pending Preliminär cards_booked Booked Bokförd cards_credit Deposit Insättning cards_foreign Foreign currency Utländsk valuta cards_match_one Link to %1$s Koppla till %1$s cards_match_many:one %1$d possible expense %1$d möjlig utgift cards_match_many:other %1$d possible expenses %1$d möjliga utgifter cards_linked_to Linked to %1$s · %2$s Kopplad till %1$s · %2$s cards_empty_title Connect your card Anslut ditt kort cards_empty_body See your purchases here and turn them into expenses in a few taps. Only you see them. Se dina köp här och gör om dem till utgifter med några tryck. Bara du ser dem. cards_connect Connect card Anslut kort cards_first_fetch Fetching your purchases… Hämtar dina köp… cards_nothing_to_handle Nothing to handle Inget att hantera cards_nothing_to_handle_body New card purchases show up here. Nya kortköp visas här. cards_filter_empty No purchases here Inga köp här cards_expiring Your card connection ends on %1$s Kortanslutningen upphör %1$s cards_expired Your card connection has ended Kortanslutningen har upphört cards_renew Renew with BankID Förnya med BankID cards_fetch_failed Could not fetch purchases. Last updated %1$s Kunde inte hämta köp. Senast uppdaterad %1$s cards_sheet_create Create expense Skapa utgift cards_sheet_matches Link to an existing expense Koppla till befintlig utgift cards_sheet_no_matches No expense with the same amount around this date Ingen utgift med samma belopp runt det här datumet cards_sheet_other Choose another expense Välj en annan utgift cards_sheet_ignore Ignore Ignorera cards_sheet_unignore Stop ignoring Sluta ignorera cards_sheet_unlink Remove link Ta bort koppling cards_sheet_open_expense Open expense Öppna utgift cards_sheet_credit_note Deposits and refunds are not expenses. Change the original expense by hand if needed. Insättningar och återbetalningar är inga utgifter. Ändra den ursprungliga utgiften för hand vid behov. cards_sheet_foreign_note The amount is in %1$s: type the amount in kronor. Beloppet är i %1$s: skriv beloppet i kronor. cards_snackbar_linked Linked Kopplad cards_snackbar_ignored Ignored Ignorerad cards_connect_title Connect card Anslut kort cards_connect_intro Choose your card. Kvitt reads your purchases but can never pay or move money. Välj ditt kort. Kvitt läser dina köp men kan aldrig betala eller flytta pengar. cards_provider_connected Connected · valid until %1$s Ansluten · giltig till %1$s cards_provider_unavailable Not set up on the server Inte konfigurerat på servern cards_history_label Fetch purchases from the last Hämta köp från de senaste cards_history_days:one %1$d day %1$d dag cards_history_days:other %1$d days %1$d dagar cards_history_note You can shorten this later. A longer period needs BankID again. Du kan korta perioden senare. En längre period kräver BankID igen. cards_connect_bankid Connect with BankID Anslut med BankID cards_waiting Waiting for BankID… Väntar på BankID… cards_waiting_body Finish in the browser and in BankID, then come back here. Slutför i webbläsaren och i BankID och kom sedan tillbaka hit. cards_connected Card connected Kortet är anslutet cards_connect_failed The card could not be connected Det gick inte att ansluta kortet cards_connect_timeout The connection attempt took too long Anslutningsförsöket tog för lång tid cards_status_active Connected Ansluten cards_status_expired Ended Har upphört cards_valid_until Valid until %1$s Giltig till %1$s cards_last_updated Last updated %1$s Senast uppdaterad %1$s cards_history_setting History when connecting Historik vid anslutning cards_history_longer_note A longer period needs BankID again En längre period kräver BankID igen cards_disconnect Disconnect Koppla från cards_disconnect_title Disconnect %1$s? Koppla från %1$s? cards_disconnect_body Purchases you have not linked or ignored are deleted. Expenses you created stay. Köp som du inte har kopplat eller ignorerat raderas. Utgifter du har skapat finns kvar. cards_disconnect_erase_all Also delete linked and ignored purchases Radera även kopplade och ignorerade köp cards_pick_title From card purchases Från kortköp cards_pick_empty No card purchases to handle Inga kortköp att hantera K2 added these keys to docs/ux/strings.csv (a8f91ee, 77 rows with nav_cards and the plural forms) and four more of its own (D-200): cards_foreign_amount ("%1$s %2$s", the bank's decimal amount and the currency, a decimal comma in Swedish), cards_connection_settings (TalkBack click label of S-23's header card: "Card connection" / "Kortanslutning"), cards_connect_offline_body (S-24's offline banner: "The list of cards comes from the server. Connect the phone to the internet." / "Listan över kort hämtas från servern. Anslut telefonen till internet.") and settings_cards_expired (S-13's subtitle of an expired connection: "Ended" / "Har upphört", D-199). Every card key is in both strings.xml files of its module. 13.4 Deliverables Phase 1 (U1): directions. In docs/ux/directions/: 2 or 3 visual directions, each a self-contained HTML file docs/ux/directions/<n>-<slug>/index.html (no external requests except Google Fonts, if a direction uses a font whose licence allows bundling in an app; the font must then also be bundleable as an Android font resource) rendering at a 411 dp wide phone frame: S-4 Home, S-7 Expense editor, S-5 Account detail, S-9 Settle up, S-11 Analytics, S-8 Expense detail with timeline, each in light and dark, in Swedish, with realistic household data (names "Jacob" and "Anna", Swedish shops and amounts; no lorem ipsum). Each direction states: name and one-line idea; colour palette (primary, secondary, tertiary, surfaces, error, "owed" and "owing" semantic colours, the 12 category colours) in light and dark with contrast ratios; typography (Material 3 type scale and why; tabular figures for amounts; the app bundles no font and uses the Material 3 default typeface, D-020, so a direction that previews another typeface has it replaced by the default in U2's design spec); shape (corner radii per component size); elevation and motion principles; iconography (Material Symbols style: outlined, rounded or sharp, weight, fill rules); how the balance header looks in its three states; how it handles 200 % font scale (one screenshot). docs/ux/directions/README.md: a comparison table of the directions (character, strengths, risks, implementation cost in Compose), and the UX agent's recommendation with reasons. PNG exports of every screen of every direction (docs/ux/directions/<n>-<slug>/png/), so the orchestrator can show them to the owner without a browser. Suggested starting points the UX agent may use, replace or merge (it must deliver at least two clearly different ones): "Kvitto": receipt-paper calm. Off-white surfaces, ink-black text, one accent colour, monospaced tabular amounts, dashed dividers like a till receipt. Expressive only in motion. "Skärgård": Material 3 Expressive with a cool sea-and-granite palette, large rounded shapes, bold balance header, playful but quiet. "Kontor": dense, utilitarian, data-forward. Neutral greys, strong typographic hierarchy, charts as the hero on Analytics, minimal decoration. Phase 2 (U2): design spec for the chosen direction. After the owner picks (and comments), in docs/ux/. The owner picked direction 3 "Kalas" with the muted palette of docs/ux/directions/3-kalas/, typeface per D-020 (D-047). U2 landed 6da6b1b, approved by the owner. docs/ux/design-spec.md is the binding design document for :core:design (§2 tokens, §3 components) and for every screen (§4, §5); this spec wins over it on rules. Amended after U2: chart bars have top corners 4 dp and bottom corners 2 dp (D-097, design-spec §2.9 and §3.10); S-7's account, date, payer and split options are four fixed rows, EditorOptionRows, and connected buttons have 8 dp side padding (D-102, design-spec §3.7 and §3.10); S-22 has no licences row (D-099, design-spec S-22); S-16's lost version (D-109) and S-22's "(schema )" (D-110), design-spec S-16 and S-22; S-11's Insights section (D-142, D-143), design-spec S-11 and §3.10; the mock-up PNGs are compressed losslessly (D-098). docs/ux/strings.csv (558 rows at U2, header included; 559 since v0.10 with ledger_settlement_label, D-068, and English "Dining" for category_default_restaurants, D-067; 578 since v0.11 with the shared keys common_ok, common_undo and editor_split_full_on_you and the module keys of M7b to M7f recorded as built, D-079; 577 since v0.16 without settings_about_licences, D-099; 562 since v0.18: M12f added home_sync_lost_title, home_sync_lost_body, home_sync_lost_deleted, home_sync_lost_show_current (D-109) and settings_about_server_version_schema (D-110) and removed the 19 keys (20 rows) that R8 found unused (a0259ab); 569 since v0.27 with the seven S-12 line-chart keys analytics_average, analytics_moving_average, analytics_vs_average_above, analytics_vs_average_below, analytics_vs_average_on, analytics_summary_line, analytics_summary_line_single (D-128); 588 since v0.31 with the 16 S-11 Insights keys analytics_insights_*, three of them plurals (19 rows, D-142, D-143); keys with the D-017 prefixes; plurals as key:one / key:other) is the source of every string resource: design-spec.md: final tokens (colour roles light and dark, category colour hex values, typography scale, shapes, spacing scale in dp, elevation, motion durations and easing), component inventory (each with anatomy, states, sizes), and for every screen S-1 to S-22: layout description, all states of §13.3, interaction details, TalkBack labels. strings.csv: every user-visible string of the app with columns key,en,sv,notes, keys in snake_case prefixed by the feature module that holds them (home_balance_owes_you, expense_save; shared strings for :core:design never start with a feature name; the app name is the only :app string; §6.2, D-017), placeholders as Android format arguments (%1$s), plurals marked in notes with their quantities. This becomes values/strings.xml and values-sv/strings.xml in M6 and M7; feature agents add no strings that are not in this file without a decisions entry. Keys recorded by D-079 (v0.11): shared common_ok, common_undo, editor_split_full_on_you ("All on you" / "Allt på dig"; ledger_settlement_label was D-068); module keys as built: analytics_granularity, analytics_measure, analytics_group_by, analytics_range_apply; settle_row_amount, settle_detail_delete, settle_detail_sync_now; expense_detail_sync_now; home_archived_expanded, home_archived_collapsed; settings_category_archived_snackbar, settings_category_unarchived_snackbar, settings_recurring_summary_none, settings_expanded, settings_collapsed, settings_partner_missing. screens/<S-id>-<slug>.png for every screen and state, light and dark, Swedish. Updated colour hex values for the 14 tokens of §9.7 (the muted Kalas values, slate and amber included), proposed as a spec change (decisions entry, spec version bump) by the orchestrator (D-051). 13.5 Out of scope for the UX sprint New features, changes to flows required by §4, changes to enums or limits, app icon production (a direction may sketch one), animations beyond descriptions, Kotlin code. 14. Contracts Contracts are what lets agents work in parallel. Each subsection is binding. The files that M1 writes from this section are listed in §14.8. A change to any contract follows §14.8. 14.1 SQLite schema v1 (server) and migrations The server schema is at version 4: the v1 DDL below (migration 0001) plus migration 0002 (§14.1.1, D-054), migration 0003 (§14.1.2, D-090) and migration 0004 (§14.1.3, D-167). This DDL is the content of contracts/schema/server-v1.sql and of the server's first migration server/crates/kvitt-server/migrations/0001_init.sql, byte for byte (a test asserts equality). Conventions: ids TEXT (UUIDv7, see the conventions at the top of this file); money INTEGER öre; timestamps TEXT in the fixed RFC 3339 form; booleans INTEGER 0/1; server_version from sync_sequence. Enum and token lists that may grow (icons, colours) are checked in code, not in DDL. Every connection sets the pragmas of §8.9. -- Kvitt server schema v1. Do not edit; add a new migration and bump the schema version (SPEC §14.8). CREATE TABLE meta ( key TEXT PRIMARY KEY NOT NULL, value TEXT NOT NULL ) STRICT; -- One global, strictly increasing counter for server_version. Exactly one row. CREATE TABLE sync_sequence ( id INTEGER PRIMARY KEY CHECK (id = 1), value INTEGER NOT NULL ) STRICT; CREATE TABLE users ( id TEXT PRIMARY KEY NOT NULL, role TEXT NOT NULL CHECK (role IN ('admin', 'member')), display_name TEXT NOT NULL CHECK (length(display_name) BETWEEN 1 AND 40), picture_version INTEGER CHECK (picture_version IS NULL OR picture_version >= 1), created_at TEXT NOT NULL, updated_at TEXT NOT NULL, server_version INTEGER NOT NULL UNIQUE ) STRICT; CREATE UNIQUE INDEX users_single_admin ON users (role) WHERE role = 'admin'; CREATE TABLE devices ( id TEXT PRIMARY KEY NOT NULL, user_id TEXT NOT NULL REFERENCES users (id), name TEXT NOT NULL CHECK (length(name) BETWEEN 1 AND 60), token_hash TEXT NOT NULL UNIQUE, fcm_token TEXT, app_version_code INTEGER, created_at TEXT NOT NULL, last_seen_at TEXT NOT NULL, revoked_at TEXT, revoked_by_user_id TEXT REFERENCES users (id) ) STRICT; CREATE INDEX devices_user ON devices (user_id); CREATE TABLE invites ( id TEXT PRIMARY KEY NOT NULL, kind TEXT NOT NULL CHECK (kind IN ('admin_setup', 'partner', 'device')), code_hash TEXT NOT NULL UNIQUE, target_user_id TEXT REFERENCES users (id), created_by_user_id TEXT REFERENCES users (id), created_at TEXT NOT NULL, expires_at TEXT NOT NULL, accepted_at TEXT, accepted_device_id TEXT REFERENCES devices (id), cancelled_at TEXT, CHECK ((kind = 'device') = (target_user_id IS NOT NULL)), CHECK ((kind = 'admin_setup') = (created_by_user_id IS NULL) OR kind = 'device') ) STRICT; CREATE TABLE accounts ( id TEXT PRIMARY KEY NOT NULL, name TEXT NOT NULL CHECK (length(name) BETWEEN 1 AND 60), name_key TEXT NOT NULL, created_by_user_id TEXT NOT NULL REFERENCES users (id), created_at TEXT NOT NULL, updated_at TEXT NOT NULL, archived_at TEXT, deleted_at TEXT, server_version INTEGER NOT NULL UNIQUE ) STRICT; -- name_key = Unicode-lowercased, trimmed name, computed in Rust. CREATE UNIQUE INDEX accounts_name_live ON accounts (name_key) WHERE deleted_at IS NULL; CREATE TABLE account_default_shares ( account_id TEXT NOT NULL REFERENCES accounts (id), user_id TEXT NOT NULL REFERENCES users (id), share_bp INTEGER NOT NULL CHECK (share_bp BETWEEN 0 AND 10000), PRIMARY KEY (account_id, user_id) ) STRICT, WITHOUT ROWID; CREATE TABLE categories ( id TEXT PRIMARY KEY NOT NULL, default_key TEXT UNIQUE CHECK (default_key IS NULL OR default_key IN ('groceries', 'restaurants', 'home', 'utilities', 'transport', 'travel', 'entertainment', 'health', 'shopping', 'other')), name TEXT CHECK (name IS NULL OR length(name) BETWEEN 1 AND 40), icon TEXT NOT NULL, color TEXT NOT NULL, sort_order INTEGER NOT NULL, created_at TEXT NOT NULL, updated_at TEXT NOT NULL, archived_at TEXT, deleted_at TEXT, server_version INTEGER NOT NULL UNIQUE, CHECK (name IS NOT NULL OR default_key IS NOT NULL) ) STRICT; CREATE TABLE recurring_templates ( id TEXT PRIMARY KEY NOT NULL, account_id TEXT NOT NULL REFERENCES accounts (id), category_id TEXT NOT NULL REFERENCES categories (id), amount_ore INTEGER NOT NULL CHECK (amount_ore BETWEEN 1 AND 1000000000), description TEXT NOT NULL CHECK (length(description) BETWEEN 1 AND 100), notes TEXT NOT NULL DEFAULT '' CHECK (length(notes) <= 1000), payer_user_id TEXT NOT NULL REFERENCES users (id), split_mode TEXT NOT NULL CHECK (split_mode IN ('default', 'ratio', 'exact', 'full')), day_of_month INTEGER NOT NULL CHECK (day_of_month BETWEEN 1 AND 31), start_period TEXT NOT NULL, end_period TEXT, paused INTEGER NOT NULL DEFAULT 0 CHECK (paused IN (0, 1)), last_generated_period TEXT, created_by_user_id TEXT NOT NULL REFERENCES users (id), updated_by_user_id TEXT NOT NULL REFERENCES users (id), created_at TEXT NOT NULL, updated_at TEXT NOT NULL, deleted_at TEXT, server_version INTEGER NOT NULL UNIQUE ) STRICT; CREATE INDEX recurring_templates_account ON recurring_templates (account_id); -- Modes ratio and full: share_bp set, share_ore NULL. Mode exact: share_ore set, share_bp NULL. Mode default: no rows. CREATE TABLE recurring_template_splits ( template_id TEXT NOT NULL REFERENCES recurring_templates (id), user_id TEXT NOT NULL REFERENCES users (id), share_bp INTEGER CHECK (share_bp IS NULL OR share_bp BETWEEN 0 AND 10000), share_ore INTEGER CHECK (share_ore IS NULL OR share_ore >= 0), PRIMARY KEY (template_id, user_id), CHECK ((share_bp IS NULL) <> (share_ore IS NULL)) ) STRICT, WITHOUT ROWID; CREATE TABLE expenses ( id TEXT PRIMARY KEY NOT NULL, account_id TEXT NOT NULL REFERENCES accounts (id), category_id TEXT NOT NULL REFERENCES categories (id), amount_ore INTEGER NOT NULL CHECK (amount_ore BETWEEN 1 AND 1000000000), description TEXT NOT NULL CHECK (length(description) BETWEEN 1 AND 100), notes TEXT NOT NULL DEFAULT '' CHECK (length(notes) <= 1000), expense_date TEXT NOT NULL, payer_user_id TEXT NOT NULL REFERENCES users (id), split_mode TEXT NOT NULL CHECK (split_mode IN ('default', 'ratio', 'exact', 'full')), recurring_template_id TEXT REFERENCES recurring_templates (id), recurring_period TEXT, import_key TEXT UNIQUE, created_by_user_id TEXT NOT NULL REFERENCES users (id), updated_by_user_id TEXT NOT NULL REFERENCES users (id), updated_by_device_id TEXT REFERENCES devices (id), created_at TEXT NOT NULL, updated_at TEXT NOT NULL, deleted_at TEXT, server_received_at TEXT NOT NULL, server_version INTEGER NOT NULL UNIQUE, CHECK ((recurring_template_id IS NULL) = (recurring_period IS NULL)) ) STRICT; CREATE UNIQUE INDEX expenses_recurring_once ON expenses (recurring_template_id, recurring_period) WHERE recurring_template_id IS NOT NULL; CREATE INDEX expenses_account ON expenses (account_id); CREATE INDEX expenses_category ON expenses (category_id); -- Exactly two rows per expense, one per household user. share_bp NULL for mode exact. CREATE TABLE expense_splits ( expense_id TEXT NOT NULL REFERENCES expenses (id), user_id TEXT NOT NULL REFERENCES users (id), share_ore INTEGER NOT NULL CHECK (share_ore >= 0), share_bp INTEGER CHECK (share_bp IS NULL OR share_bp BETWEEN 0 AND 10000), PRIMARY KEY (expense_id, user_id) ) STRICT, WITHOUT ROWID; CREATE TABLE settlements ( id TEXT PRIMARY KEY NOT NULL, from_user_id TEXT NOT NULL REFERENCES users (id), to_user_id TEXT NOT NULL REFERENCES users (id), amount_ore INTEGER NOT NULL CHECK (amount_ore BETWEEN 1 AND 1000000000), settlement_date TEXT NOT NULL, note TEXT NOT NULL DEFAULT '' CHECK (length(note) <= 200), import_key TEXT UNIQUE, created_by_user_id TEXT NOT NULL REFERENCES users (id), updated_by_user_id TEXT NOT NULL REFERENCES users (id), updated_by_device_id TEXT REFERENCES devices (id), created_at TEXT NOT NULL, updated_at TEXT NOT NULL, deleted_at TEXT, server_received_at TEXT NOT NULL, server_version INTEGER NOT NULL UNIQUE, CHECK (from_user_id <> to_user_id) ) STRICT; CREATE TABLE settlement_allocations ( settlement_id TEXT NOT NULL REFERENCES settlements (id), account_id TEXT NOT NULL REFERENCES accounts (id), amount_ore INTEGER NOT NULL CHECK (amount_ore >= 1), PRIMARY KEY (settlement_id, account_id) ) STRICT, WITHOUT ROWID; CREATE INDEX settlement_allocations_account ON settlement_allocations (account_id); -- Append-only. changes is a JSON array of {"field","old","new"} (SPEC §14.4.7). CREATE TABLE audit_log ( id TEXT PRIMARY KEY NOT NULL, entity_type TEXT NOT NULL CHECK (entity_type IN ('expense', 'settlement')), entity_id TEXT NOT NULL, action TEXT NOT NULL CHECK (action IN ('create', 'update', 'delete')), source TEXT NOT NULL CHECK (source IN ('app', 'recurring', 'import')), actor_user_id TEXT NOT NULL REFERENCES users (id), actor_device_id TEXT REFERENCES devices (id), client_at TEXT NOT NULL, server_at TEXT NOT NULL, changes TEXT NOT NULL, server_version INTEGER NOT NULL UNIQUE ) STRICT; CREATE INDEX audit_log_entity ON audit_log (entity_type, entity_id); -- Idempotency of POST /sync. Rows older than 90 days are pruned daily. CREATE TABLE sync_mutations ( mutation_id TEXT PRIMARY KEY NOT NULL, device_id TEXT NOT NULL REFERENCES devices (id), entity_type TEXT NOT NULL CHECK (entity_type IN ('expense', 'settlement')), entity_id TEXT NOT NULL, result TEXT NOT NULL, received_at TEXT NOT NULL ) STRICT; CREATE INDEX sync_mutations_received ON sync_mutations (received_at); INSERT INTO sync_sequence (id, value) VALUES (1, 10); INSERT INTO meta (key, value) VALUES ('schema_version', '1'); INSERT INTO meta (key, value) VALUES ('sync_epoch', lower(hex(randomblob(16)))); INSERT INTO categories (id, default_key, name, icon, color, sort_order, created_at, updated_at, archived_at, deleted_at, server_version) VALUES ('01920000-0000-7000-8000-000000000001', 'groceries', NULL, 'shopping_cart', 'green', 10, '2026-10-17T00:00:00.000Z', '2026-10-17T00:00:00.000Z', NULL, NULL, 1), ('01920000-0000-7000-8000-000000000002', 'restaurants', NULL, 'restaurant', 'orange', 20, '2026-10-17T00:00:00.000Z', '2026-10-17T00:00:00.000Z', NULL, NULL, 2), ('01920000-0000-7000-8000-000000000003', 'home', NULL, 'home', 'brown', 30, '2026-10-17T00:00:00.000Z', '2026-10-17T00:00:00.000Z', NULL, NULL, 3), ('01920000-0000-7000-8000-000000000004', 'utilities', NULL, 'bolt', 'yellow', 40, '2026-10-17T00:00:00.000Z', '2026-10-17T00:00:00.000Z', NULL, NULL, 4), ('01920000-0000-7000-8000-000000000005', 'transport', NULL, 'directions_car', 'blue', 50, '2026-10-17T00:00:00.000Z', '2026-10-17T00:00:00.000Z', NULL, NULL, 5), ('01920000-0000-7000-8000-000000000006', 'travel', NULL, 'flight', 'teal', 60, '2026-10-17T00:00:00.000Z', '2026-10-17T00:00:00.000Z', NULL, NULL, 6), ('01920000-0000-7000-8000-000000000007', 'entertainment', NULL, 'movie', 'purple', 70, '2026-10-17T00:00:00.000Z', '2026-10-17T00:00:00.000Z', NULL, NULL, 7), ('01920000-0000-7000-8000-000000000008', 'health', NULL, 'medical_services', 'red', 80, '2026-10-17T00:00:00.000Z', '2026-10-17T00:00:00.000Z', NULL, NULL, 8), ('01920000-0000-7000-8000-000000000009', 'shopping', NULL, 'shopping_bag', 'pink', 90, '2026-10-17T00:00:00.000Z', '2026-10-17T00:00:00.000Z', NULL, NULL, 9), ('01920000-0000-7000-8000-00000000000a', 'other', NULL, 'category', 'grey', 100, '2026-10-17T00:00:00.000Z', '2026-10-17T00:00:00.000Z', NULL, NULL, 10); Server-side rules on top of the DDL: Every write transaction starts with BEGIN IMMEDIATE. Taking a server_version is UPDATE sync_sequence SET value = value + 1 WHERE id = 1 RETURNING value inside that transaction. At most two rows in users (checked in code; household_full). meta.sync_epoch is replaced by kvitt-server rotate-epoch with a new lower(hex(randomblob(16))). No row of users, devices, accounts, categories, recurring_templates, expenses, settlements or audit_log is ever hard-deleted. Child rows (account_default_shares, recurring_template_splits, expense_splits, settlement_allocations) are replaced (delete and insert) when their parent is updated. Card rows (§14.1.3): card_connections are never deleted; card_purchases become content-erased tombstones (D-167); card_auth_attempts are pruned 7 days after creation by the same 04:00 job. invites rows are never deleted; sync_mutations rows are pruned after 90 days by a daily job at 04:00 Europe/Stockholm (DST-aware, always local 04:00) that deletes rows whose received_at is strictly older than 90 days; a row exactly 90 days old is kept (D-021, D-039). 14.1.1 Migration 0002: schema version 2 (D-054) Migration 0002 adds the four default categories housing, insurance, children and fees of AC-7.2 to every database, existing ones (the development stack included) on upgrade and new ones right after 0001. The SQL below is the content of the contract file contracts/schema/migrations/0002_categories_v2.sql as M12a committed it (aa765bb; the file wins over this copy) and of the server migration server/crates/kvitt-server/migrations/0002_categories_v2.sql, byte for byte (a test asserts equality, as for 0001); contracts/schema/server-v1.sql stays unchanged. Every later migration follows the same pattern: contracts/schema/migrations/<NNNN>_<name>.sql is its locked text. The v1 CHECK on categories.default_key lists ten keys and SQLite cannot alter a CHECK, so the migration rebuilds categories with the fourteen keys (the ten of v1 followed by the four new ones) and otherwise the same columns and constraints, keeping every row unchanged (custom categories, renames, archive state, server_version). sqlx runs the migration in one transaction on a connection with foreign_keys = ON (§8.9), where PRAGMA foreign_keys cannot change. PRAGMA defer_foreign_keys = ON defers the checks to the commit; the rows are copied out, the table dropped and recreated under its own name, and the rows copied back, so every reference from expenses and recurring_templates resolves again before the commit. Each new row takes its server_version from the global sequence (§14.1 rules), so phones receive the four rows in their next pull like any other change. Ids 01920000-0000-7000-8000-000000000011 to …014, created_at = updated_at = 2026-10-18T00:00:00.000Z, name null. meta.schema_version becomes 2; the server's SCHEMA_VERSION constant (E-1) becomes 2, and the importer's check (§10.8), which reads that constant, follows. The Room schema is unchanged (version 1): category rows reach the phone through sync (§14.2). -- Kvitt server schema v2: four new default categories (housing, insurance, children, fees). Do not edit; add a new -- migration and bump the schema version (SPEC §14.8). Applied on top of server-v1.sql (0001_init.sql). -- -- The default_key CHECK of categories cannot be altered in place in SQLite, so the table is rebuilt: copy the rows -- aside, drop the table, recreate it with the new CHECK and copy the rows back, ids and server_version unchanged. -- The migration runs inside one transaction (sqlx wraps every migration in one) with foreign_keys = ON (SPEC §8.9). -- defer_foreign_keys = ON lets expenses and recurring_templates point at categories while the table is briefly -- absent; the deferred check at commit still fails the migration if any reference is left dangling. It resets -- itself when the transaction ends. No other table, index or trigger refers to categories by anything but name. PRAGMA defer_foreign_keys = ON; CREATE TABLE categories_v1_copy AS SELECT * FROM categories; DROP TABLE categories; CREATE TABLE categories ( id TEXT PRIMARY KEY NOT NULL, default_key TEXT UNIQUE CHECK (default_key IS NULL OR default_key IN ('groceries', 'restaurants', 'home', 'utilities', 'transport', 'travel', 'entertainment', 'health', 'shopping', 'other', 'housing', 'insurance', 'children', 'fees')), name TEXT CHECK (name IS NULL OR length(name) BETWEEN 1 AND 40), icon TEXT NOT NULL, color TEXT NOT NULL, sort_order INTEGER NOT NULL, created_at TEXT NOT NULL, updated_at TEXT NOT NULL, archived_at TEXT, deleted_at TEXT, server_version INTEGER NOT NULL UNIQUE, CHECK (name IS NOT NULL OR default_key IS NOT NULL) ) STRICT; INSERT INTO categories (id, default_key, name, icon, color, sort_order, created_at, updated_at, archived_at, deleted_at, server_version) SELECT id, default_key, name, icon, color, sort_order, created_at, updated_at, archived_at, deleted_at, server_version FROM categories_v1_copy; DROP TABLE categories_v1_copy; -- Each new row takes the next server_version from the global sequence, as every server write does (SPEC §14.1), so -- phones receive the rows on their next pull whatever their cursor. UPDATE sync_sequence SET value = value + 1 WHERE id = 1; INSERT INTO categories (id, default_key, name, icon, color, sort_order, created_at, updated_at, archived_at, deleted_at, server_version) SELECT '01920000-0000-7000-8000-000000000011', 'housing', NULL, 'key', 'indigo', 25, '2026-10-18T00:00:00.000Z', '2026-10-18T00:00:00.000Z', NULL, NULL, value FROM sync_sequence WHERE id = 1; UPDATE sync_sequence SET value = value + 1 WHERE id = 1; INSERT INTO categories (id, default_key, name, icon, color, sort_order, created_at, updated_at, archived_at, deleted_at, server_version) SELECT '01920000-0000-7000-8000-000000000012', 'insurance', NULL, 'shield', 'slate', 45, '2026-10-18T00:00:00.000Z', '2026-10-18T00:00:00.000Z', NULL, NULL, value FROM sync_sequence WHERE id = 1; UPDATE sync_sequence SET value = value + 1 WHERE id = 1; INSERT INTO categories (id, default_key, name, icon, color, sort_order, created_at, updated_at, archived_at, deleted_at, server_version) SELECT '01920000-0000-7000-8000-000000000013', 'children', NULL, 'child_care', 'lime', 85, '2026-10-18T00:00:00.000Z', '2026-10-18T00:00:00.000Z', NULL, NULL, value FROM sync_sequence WHERE id = 1; UPDATE sync_sequence SET value = value + 1 WHERE id = 1; INSERT INTO categories (id, default_key, name, icon, color, sort_order, created_at, updated_at, archived_at, deleted_at, server_version) SELECT '01920000-0000-7000-8000-000000000014', 'fees', NULL, 'account_balance', 'amber', 95, '2026-10-18T00:00:00.000Z', '2026-10-18T00:00:00.000Z', NULL, NULL, value FROM sync_sequence WHERE id = 1; UPDATE meta SET value = '2' WHERE key = 'schema_version'; 14.1.2 Migration 0003: schema version 3 (D-090) Migration 0003 adds the column devices.app_version_name (the app's versionName, from the request header X-Kvitt-App-Version-Name, §14.3.1), written like app_version_code (§8.2). The SQL below is the content of the contract file contracts/schema/migrations/0003_device_version_name.sql as M12e committed it (8c60715; the file wins over this copy) and of the server migration server/crates/kvitt-server/migrations/0003_device_version_name.sql, byte for byte (a test asserts equality, as for 0001 and 0002). Existing devices keep every column and get NULL until their next request that carries the header (at most once per hour, §8.2); E-3 stores it at pairing. meta.schema_version becomes 3; the server's SCHEMA_VERSION constant (E-1) becomes 3, and the importer's check (§10.8) follows. A migration test upgrades a v2 database in use to schema 3 and asserts that every row is kept. The Room schema is unchanged (version 1): the phone stores no devices (§14.2). -- Kvitt server schema v3: the app's versionName per device (devices.app_version_name), sent in the -- X-Kvitt-App-Version-Name header and written like app_version_code (SPEC §14.3.1, §8.2). Do not edit; add a new -- migration and bump the schema version (SPEC §14.8). Applied on top of 0002_categories_v2.sql. -- -- Existing devices keep every column and get NULL until their next request that carries the header. ALTER TABLE devices ADD COLUMN app_version_name TEXT CHECK (app_version_name IS NULL OR length(app_version_name) BETWEEN 1 AND 32); UPDATE meta SET value = '3' WHERE key = 'schema_version'; 14.1.3 Migration 0004: schema version 4 (D-167) Migration 0004 adds the card-purchase tables of §9.12. The SQL below is the intended content of the contract file contracts/schema/migrations/0004_card_purchases.sql, which K1 commits (the file wins over this copy once committed; K1 may only make changes its report justifies, recorded by a docs agent), and of the server migration server/crates/kvitt-server/migrations/0004_card_purchases.sql, byte for byte (a test asserts equality, as for 0001 to 0003). K1 committed both files byte-identical to the copy below (671c00d, v0.38); server schema 4 is in code. No existing table changes: the household tables, server_version and GET /sync are untouched (card rows are not household rows, D-161). card_version comes from the new one-row card_sequence, taken like server_version (UPDATE card_sequence SET value = value + 1 WHERE id = 1 RETURNING value) inside the write's BEGIN IMMEDIATE transaction, so a card cursor never sees a gap that later fills (§6.4). Tombstones (D-167): a card purchase is never hard-deleted while the database lives; a deleted one keeps id, user_id, connection_id and its new card_version, gets deleted_at, and has its content erased (provider_ref '', merchant '', amount_ore, original_amount, original_currency, booking_date and expense_id null, ignored 0, purchase_date kept as 1970-01-01), so a phone learns of the deletion and nothing of the purchase is left. Connections are never deleted; a disconnected one keeps only its id, user, provider, history and timestamps. card_auth_attempts rows are pruned 7 days after creation by the 04:00 job of §14.1 (they are not referenced by anything a client keeps). The validity rules of §9.6 and §9.12 are checked in code; the CHECKs below are a backstop, as for the household tables (enums that may grow, such as provider ids and history choices, are not listed in DDL). meta.schema_version becomes 4; the server's SCHEMA_VERSION constant (E-1) becomes 4, and the importer's check (§10.8) follows. A migration test upgrades a v3 database in use (users, devices, accounts, expenses, audit entries) to schema 4 and asserts that every row is kept and that the new tables are empty except card_sequence. The Room schema becomes version 2 (§14.2.3): the phone mirrors its own user's card rows. -- Kvitt server schema v4: card purchases (SPEC §9.12, FR-22, D-167). Do not edit; add a new migration and bump the -- schema version (SPEC §14.8). Applied on top of 0003_device_version_name.sql. -- -- Card data is private to the card holder (D-161): none of these rows is in the household sync stream (GET /sync), the -- audit log or a push. Card rows carry card_version from their own sequence and are read through GET /cards/sync. CREATE TABLE card_sequence ( id INTEGER PRIMARY KEY CHECK (id = 1), value INTEGER NOT NULL ) STRICT; INSERT INTO card_sequence (id, value) VALUES (1, 0); -- One connection per user and card provider. session_id is an Enable Banking session: a credential usable only with the -- application's private key, which is never in the database or a backup (D-161). Erased when disconnected. CREATE TABLE card_connections ( id TEXT PRIMARY KEY NOT NULL, user_id TEXT NOT NULL REFERENCES users (id), provider_id TEXT NOT NULL CHECK (length(provider_id) BETWEEN 1 AND 64), status TEXT NOT NULL CHECK (status IN ('active', 'expired', 'disconnected')), session_id TEXT, account_uid TEXT, valid_until TEXT, history_days INTEGER NOT NULL CHECK (history_days BETWEEN 1 AND 365), last_fetch_at TEXT, last_fetch_error TEXT, last_user_fetch_at TEXT, background_fetches TEXT NOT NULL DEFAULT '[]', created_at TEXT NOT NULL, updated_at TEXT NOT NULL, card_version INTEGER NOT NULL UNIQUE, CHECK ((status = 'disconnected') = (session_id IS NULL)) ) STRICT; CREATE UNIQUE INDEX card_connections_user_provider ON card_connections (user_id, provider_id); -- Single-use authorisation attempts (D-162); state is stored only as its SHA-256 hash. Pruned 7 days after creation. CREATE TABLE card_auth_attempts ( id TEXT PRIMARY KEY NOT NULL, user_id TEXT NOT NULL REFERENCES users (id), device_id TEXT NOT NULL REFERENCES devices (id), provider_id TEXT NOT NULL CHECK (length(provider_id) BETWEEN 1 AND 64), client TEXT NOT NULL CHECK (client IN ('android', 'web')), state_hash TEXT NOT NULL UNIQUE, history_days INTEGER NOT NULL CHECK (history_days BETWEEN 1 AND 365), status TEXT NOT NULL CHECK (status IN ('pending', 'connected', 'failed', 'expired')), failure TEXT, connection_id TEXT REFERENCES card_connections (id), created_at TEXT NOT NULL, expires_at TEXT NOT NULL, finished_at TEXT ) STRICT; CREATE INDEX card_auth_attempts_created ON card_auth_attempts (created_at); -- Purchases as the bank reports them, mapped per SPEC §9.12 CP-7. amount_ore is null only for a non-SEK purchase -- (original_amount and original_currency then set) and for a tombstone. A tombstone has its content erased (D-167). CREATE TABLE card_purchases ( id TEXT PRIMARY KEY NOT NULL, user_id TEXT NOT NULL REFERENCES users (id), connection_id TEXT NOT NULL REFERENCES card_connections (id), provider_ref TEXT NOT NULL, status TEXT NOT NULL CHECK (status IN ('pending', 'booked')), direction TEXT NOT NULL CHECK (direction IN ('debit', 'credit')), purchase_date TEXT NOT NULL, booking_date TEXT, amount_ore INTEGER CHECK (amount_ore IS NULL OR amount_ore >= 1), original_amount TEXT, original_currency TEXT CHECK (original_currency IS NULL OR length(original_currency) = 3), merchant TEXT NOT NULL CHECK (length(merchant) <= 140), expense_id TEXT REFERENCES expenses (id), ignored INTEGER NOT NULL DEFAULT 0 CHECK (ignored IN (0, 1)), created_at TEXT NOT NULL, updated_at TEXT NOT NULL, deleted_at TEXT, card_version INTEGER NOT NULL UNIQUE, CHECK (NOT (ignored = 1 AND expense_id IS NOT NULL)), CHECK (deleted_at IS NOT NULL OR (amount_ore IS NULL) = (original_currency IS NOT NULL)) ) STRICT; CREATE UNIQUE INDEX card_purchases_ref ON card_purchases (connection_id, provider_ref) WHERE deleted_at IS NULL; CREATE UNIQUE INDEX card_purchases_expense_once ON card_purchases (user_id, expense_id) WHERE expense_id IS NOT NULL AND deleted_at IS NULL; CREATE INDEX card_purchases_user_version ON card_purchases (user_id, card_version); CREATE INDEX card_purchases_expense ON card_purchases (expense_id); UPDATE meta SET value = '4' WHERE key = 'schema_version'; 14.2 Room entities (phone) Database class KvittDatabase in :data, file name kvitt.db, version 2 (version 1 until D-173, v0.35), exportSchema = true with schemas in android/data/schemas/ (committed). Package se.hagstedt.kvitt.data.db. Room 3 (androidx.room3, KSP only) on an SQLiteDriver with sqlite-bundled (D-012). M2b created the entities and KvittDatabase version 1; the exported android/data/schemas/se.hagstedt.kvitt.data.db.KvittDatabase/1.json is a contract file (§14.8). Rules: Table and column names are identical to the server's (§14.1) where the column exists on both. Kotlin properties are camelCase with @ColumnInfo(name = "snake_case"). No foreign keys in Room: sync pages may deliver a child before its parent (a parent updated later carries a higher server_version). Queries that feed the UI join and skip rows whose references do not resolve yet. Server-only columns are not mirrored: token_hash, fcm_token, name_key, import_key, server_received_at, updated_by_device_id, code_hash. Tables devices, invites, meta, sync_sequence, sync_mutations are not mirrored. Card tables (D-173): only the signed-in user's own rows, without user_id, session_id, account_uid, last_user_fetch_at, background_fetches and provider_ref; card_auth_attempts and card_sequence are not mirrored. Timestamps are String in the fixed RFC 3339 form; dates String YYYY-MM-DD; money Long; bp Int; booleans Boolean. local_updated_at (Long, epoch milliseconds, phone clock) is set on every local write and on every row written from the network. It orders the push queue and is never sent. 14.2.1 Mirrored tables Entity class Table Columns (server columns unless marked local) Primary key Indices UserEntity users id, role, display_name, picture_version?, created_at, updated_at, server_version, local local_updated_at id none AccountEntity accounts id, name, created_by_user_id, created_at, updated_at, archived_at?, deleted_at?, server_version, local local_updated_at id created_at AccountDefaultShareEntity account_default_shares account_id, user_id, share_bp (account_id, user_id) none CategoryEntity categories id, default_key?, name?, icon, color, sort_order, created_at, updated_at, archived_at?, deleted_at?, server_version, local local_updated_at id none RecurringTemplateEntity recurring_templates every server column, plus next_occurrence_date? (from the wire), local local_updated_at id account_id RecurringTemplateSplitEntity recurring_template_splits template_id, user_id, share_bp?, share_ore? (template_id, user_id) none ExpenseEntity expenses id, account_id, category_id, amount_ore, description, notes, expense_date, payer_user_id, split_mode, recurring_template_id?, recurring_period?, created_by_user_id? (null until the server accepted the create), updated_by_user_id?, created_at, updated_at, deleted_at?, server_version? (null until accepted); local pending, pending_mutation_id?, local_updated_at id account_id, expense_date, pending ExpenseSplitEntity expense_splits expense_id, user_id, share_ore, share_bp? (expense_id, user_id) none SettlementEntity settlements id, from_user_id, to_user_id, amount_ore, settlement_date, note, created_by_user_id?, updated_by_user_id?, created_at, updated_at, deleted_at?, server_version?; local pending, pending_mutation_id?, local_updated_at id settlement_date, pending SettlementAllocationEntity settlement_allocations settlement_id, account_id, amount_ore (settlement_id, account_id) account_id CardConnectionEntity (v2, D-173) card_connections id, provider_id, status, history_days, valid_until?, last_fetch_at?, last_fetch_error?, created_at, updated_at, card_version, local local_updated_at id none CardPurchaseEntity (v2, D-173) card_purchases id, connection_id, status, direction, purchase_date, booking_date?, amount_ore?, original_amount?, original_currency?, merchant, expense_id?, ignored, created_at, updated_at, deleted_at?, card_version; local pending, local_updated_at id purchase_date, expense_id, pending AuditEntryEntity audit_log id, entity_type, entity_id, action, source, actor_user_id, client_at, server_at, changes (JSON text as received), server_version id (entity_type, entity_id) Local-only semantics on expenses and settlements: pending = true means the row has a local change not yet accepted by the server. Every local create, edit or delete sets pending = true, sets a new UUIDv7 pending_mutation_id, sets updated_at to the phone's current time in the fixed RFC 3339 form (and created_at on create), and sets local_updated_at. A local delete sets deleted_at = updated_at = now. The row stays as a tombstone. The pending-changes count (AC-15.4) is count(expenses where pending) + count(settlements where pending); pending card rows are not counted (they are the holder's own and need no attention, CP-9). Card purchases follow the same pattern for the holder's link and ignore changes (CP-9): a local link, unlink or setIgnored writes expense_id and ignored, sets pending = true and local_updated_at; the card cycle sends PUT /cards/purchases/{id} (E-44) for each pending row and, on 200, overwrites the row with the answer and clears pending; on not_found with field expense_id (the expense is not on the server yet) it stays pending for the next cycle; on not_found for the purchase it deletes the local row; on expense_already_linked or validation_failed it takes the server's state at the next pull and clears pending: the row's card_version is reset to 0 and card_sync_state.cursor moved back to just before the row's version when it is ahead, so the unchanged server row is pulled again (D-192). A link whose expense is not on the phone or is deleted there is cleared before E-44, and every link to an expense is cleared when the phone deletes it locally or removes it after a rejection (D-193). A card pull skips a pending local row, as §14.4.2 step 3 does. Deleted purchases (tombstones) are deleted locally. 14.2.2 Local-only tables Entity class Table Columns Primary key SyncStateEntity sync_state id (always 1), cursor Long (last applied next_since, 0 initially), epoch String?, last_success_at String?, last_attempt_at String?, last_error_code String? (an error code of §14.3.2 or network), clock_skew Boolean id CardSyncStateEntity (v2, D-173) card_sync_state id (always 1), cursor Long (last applied next_since of E-40, 0 initially), last_success_at String? id SyncRejectionEntity sync_rejections mutation_id, entity_type, entity_id, reason (§14.4.6), message, rejected_payload (JSON of the entity as pushed), server_current (JSON or null), rejected_at String, dismissed Boolean mutation_id Per-phone preferences (last used account, last used category per account, "install unknown apps" explanation shown, the installed version code that received a 426 protocol_unsupported, D-043, and the last card catalogue of E-36 as JSON under card_providers, D-194) live in DataStore prefs.preferences_pb, not Room. The pairing status lives in auth.preferences_pb with the token (§8.2, D-043). 14.2.3 Migrations Version 1 has no migrations. Every later Room version adds a Migration and a migration test in :data (CLAUDE.md), and is a contract change (§14.8). Version 2 (D-173, K2): MIGRATION_1_2 creates card_connections, card_purchases and card_sync_state (with the row id 1, cursor 0) and changes no existing table; its test opens a version 1 database built from the exported 1.json holding users, accounts, categories, expenses, settlements, audit entries, a pending expense and a rejection, migrates it, and asserts every row is kept and the new tables exist as in the exported 2.json. The revoke wipe (AC-3.3) deletes the card tables with the rest. Landed by K2 (a8f91ee): KvittDatabase version 2 with MIGRATION_1_2, the exported android/data/schemas/se.hagstedt.kvitt.data.db.KvittDatabase/2.json committed (a contract file, §14.8) and the migration test in :data's MigrationTest. Room 3 migrations operate on an SQLiteConnection (the driver API), not on a SupportSQLiteDatabase (D-012). 14.2.4 UI contract: types and repository interfaces in :core:model Package se.hagstedt.kvitt.model. Features see only these. :data implements them; :core:fakes fakes them. Flows are cold kotlinx.coroutines.flow.Flow; suspend functions are main-safe. // Ids and enums @JvmInline value class UserId(val value: String) @JvmInline value class AccountId(val value: String) @JvmInline value class CategoryId(val value: String) @JvmInline value class ExpenseId(val value: String) @JvmInline value class SettlementId(val value: String) @JvmInline value class TemplateId(val value: String) @JvmInline value class DeviceId(val value: String) @JvmInline value class InviteId(val value: String) enum class Role { ADMIN, MEMBER } enum class SplitMode { DEFAULT, RATIO, EXACT, FULL } enum class InviteKind { ADMIN_SETUP, PARTNER, DEVICE } enum class EntityType { EXPENSE, SETTLEMENT } enum class AuditAction { CREATE, UPDATE, DELETE } enum class AuditSource { APP, RECURRING, IMPORT } enum class DefaultCategoryKey { GROCERIES, RESTAURANTS, HOUSING, HOME, UTILITIES, INSURANCE, TRANSPORT, TRAVEL, ENTERTAINMENT, HEALTH, CHILDREN, SHOPPING, FEES, OTHER } // AC-7.2 order (D-054) enum class ColorToken { GREEN, ORANGE, BROWN, YELLOW, BLUE, TEAL, PURPLE, RED, PINK, GREY, INDIGO, LIME, SLATE, AMBER } enum class RangePreset { THIS_MONTH, LAST_3_MONTHS, LAST_6_MONTHS, LAST_12_MONTHS, THIS_YEAR, ALL_TIME, CUSTOM } enum class Granularity { MONTH, WEEK } enum class Measure { HOUSEHOLD, MY_SHARE } enum class GroupBy { CATEGORY, ACCOUNT } enum class SyncRejectionReason { STALE, DELETED, VALIDATION_FAILED, REFERENCE_NOT_FOUND, CLOCK_SKEW } // Wire value of every enum = lowercase name (SplitMode.DEFAULT <-> "default"). Icon tokens are Strings from CategoryIcons.ALL (§9.7). object CategoryIcons { val ALL: List<String> /* the 33 tokens of §9.7, in that order */ } // Plain records data class User(val id: UserId, val role: Role, val displayName: String, val pictureVersion: Int?) data class Account(val id: AccountId, val name: String, val defaultShares: Map<UserId, Int>, val createdAt: String, val archived: Boolean) data class Category(val id: CategoryId, val defaultKey: DefaultCategoryKey?, val customName: String?, val icon: String, val color: ColorToken, val sortOrder: Int, val archived: Boolean) data class Share(val userId: UserId, val shareOre: Long, val shareBp: Int?) // Results sealed interface OnlineResult<out T> { data class Ok<T>(val value: T) : OnlineResult<T> data object Offline : OnlineResult<Nothing> data class Failed(val code: String, val field: String?) : OnlineResult<Nothing> // code from §14.3.2, or "network" when the server could not be reached (D-029) } sealed interface SaveResult<out T> { data class Saved<T>(val id: T) : SaveResult<T> data class Invalid(val errors: List<FieldError>) : SaveResult<Nothing> } data class FieldError(val field: String, val error: String) // error = a domain error token of §14.5.3, "required", or "validation_failed" for a §9.6 rule without a domain token // Session and onboarding (S-1, S-2, S-3, S-18) data class Pairing(val user: User, val inviteKind: InviteKind) // v0.13, D-086: the E-3 invite_kind; an unknown wire value reads as DEVICE sealed interface SessionState { data object Unpaired : SessionState data class Paired(val me: User, val partner: User?, val deviceId: DeviceId) : SessionState data object Revoked : SessionState data object Unrecognised : SessionState // 401 unauthorized: pair again, data kept (§14.4.8) } interface SessionRepository { val session: Flow<SessionState> suspend fun pair(serverUrl: String, code: String, displayName: String?, deviceName: String): OnlineResult<Pairing> // v0.13, D-086 suspend fun acknowledgeRevoked() // wipes local data (AC-3.3) and moves to Unpaired } // Balances shared by several screens. netOre is the viewer's net (§9.3): > 0 partner owes viewer. data class BalanceView(val netOre: Long, val partner: User) // Home (S-4) data class AccountSummary(val account: Account, val netOre: Long, val expensesThisMonth: Int) data class SyncSummary(val lastSuccessAt: String?, val pendingCount: Int, val rejectedCount: Int, val clockSkew: Boolean, val running: Boolean, val lastAttemptFailed: Boolean) // lastAttemptFailed: v0.13, D-088 data class HomeState(val me: User, val partner: User?, val global: BalanceView?, val active: List<AccountSummary>, val archived: List<AccountSummary>, val sync: SyncSummary, val update: UpdateInfo?) interface HomeRepository { fun home(): Flow<HomeState> } // Ledger rows (S-5, S-12) sealed interface ExpenseEffect { data class Lent(val ore: Long) : ExpenseEffect data class Borrowed(val ore: Long) : ExpenseEffect data object NotInvolved : ExpenseEffect data object PaidForYourself : ExpenseEffect } sealed interface LedgerRow { data class ExpenseRow(val id: ExpenseId, val date: String, val description: String, val category: Category, val amountOre: Long, val effect: ExpenseEffect, val pending: Boolean) : LedgerRow data class SettlementRow(val id: SettlementId, val date: String, val from: User, val to: User, val amountOre: Long, val accountCount: Int, val pending: Boolean) : LedgerRow // amountOre: in an account's list (S-5) the allocation to that account, elsewhere the total (AC-11.7); accountCount: allocations of the whole settlement } data class LedgerMonth(val period: String, val householdSpendOre: Long, val rows: List<LedgerRow>) // Accounts (S-5, S-6) data class AccountDetailState(val account: Account, val balance: BalanceView, val months: List<LedgerMonth>, val deletable: Boolean, val users: List<User>) interface AccountRepository { fun detail(id: AccountId): Flow<AccountDetailState?> fun all(): Flow<List<Account>> suspend fun create(name: String, defaultShares: Map<UserId, Int>): OnlineResult<AccountId> suspend fun update(id: AccountId, name: String, defaultShares: Map<UserId, Int>): OnlineResult<Unit> suspend fun setArchived(id: AccountId, archived: Boolean): OnlineResult<Unit> suspend fun delete(id: AccountId): OnlineResult<Unit> } // Expenses (S-7, S-8) data class ExpenseDraft(val id: ExpenseId?, val accountId: AccountId?, val categoryId: CategoryId?, val amountOre: Long?, val description: String, val notes: String, val date: String, val payer: UserId, val mode: SplitMode, val ratioBp: Map<UserId, Int>?, val exactOre: Map<UserId, Long>?, val fullOn: UserId?) data class ExpenseEditorOptions(val me: User, val partner: User, val accounts: List<Account>, val categories: List<Category>, val defaultAccountId: AccountId?, val defaultCategoryFor: Map<AccountId, CategoryId>, val today: String, val frequentCategoryIds: Map<AccountId, List<CategoryId>>) // frequentCategoryIds: v0.9, D-059 data class TimelineLine(val actor: User?, val action: AuditAction, val source: AuditSource, val clientAt: String, val changes: List<FieldChange>, val pendingLocal: Boolean) data class FieldChange(val field: String, val oldDisplay: String?, val newDisplay: String?) // ids already resolved to names; amounts and dates raw (öre as String, ISO date), formatted by the UI data class ExpenseDetailState(val id: ExpenseId, val account: Account, val category: Category, val amountOre: Long, val description: String, val notes: String, val date: String, val payer: User, val mode: SplitMode, val shares: List<Share>, val recurringTemplateName: String?, val deleted: Boolean, val pending: Boolean, val timeline: List<TimelineLine>) interface ExpenseRepository { fun editorOptions(): Flow<ExpenseEditorOptions> suspend fun load(id: ExpenseId): ExpenseDraft? fun preview(draft: ExpenseDraft): List<Share>? // null while the draft cannot be computed suspend fun save(draft: ExpenseDraft): SaveResult<ExpenseId> suspend fun delete(id: ExpenseId) fun detail(id: ExpenseId): Flow<ExpenseDetailState?> suspend fun suggestCategory(accountId: AccountId?, description: String): CategoryId? // §9.11, D-049; null only while the phone holds no categories } // Settlements (S-9, S-10) data class AllocationLine(val account: Account, val payerNetOre: Long, val amountOre: Long, val overSettles: Boolean) data class UntouchedAccount(val account: Account, val payerNetOre: Long) // v0.13, D-093 data class SettleState(val payer: User, val recipient: User, val amountOre: Long?, val lines: List<AllocationLine>, val remainingOre: Long, val canConfirm: Boolean, val date: String, val note: String, val untouched: List<UntouchedAccount>) // untouched: v0.13, D-093 data class SettleRequest(val editing: SettlementId?, val payer: UserId, val amountOre: Long?, val fixedAccount: AccountId?, val allocations: Map<AccountId, Long>?, val date: String, val note: String) data class SettlementDetailState(val id: SettlementId, val from: User, val to: User, val amountOre: Long, val date: String, val note: String, val allocations: List<Pair<Account, Long>>, val deleted: Boolean, val pending: Boolean, val timeline: List<TimelineLine>) interface SettlementRepository { suspend fun start(editing: SettlementId?, fixedAccount: AccountId?): SettleState? // defaults per AC-11.3 / AC-11.4; null without a paired session or partner (v0.18, D-111) suspend fun recompute(request: SettleRequest): SettleState? // allocations == null: propose (§9.4); else validate and warn; null as start (D-111) // save without a session or partner: SaveResult.Invalid([FieldError("payer", "validation_failed")]); no method throws (D-111) suspend fun save(request: SettleRequest): SaveResult<SettlementId> suspend fun delete(id: SettlementId) fun detail(id: SettlementId): Flow<SettlementDetailState?> } // Analytics (S-11, S-12) data class AnalyticsFilter(val preset: RangePreset, val customStart: String?, val customEnd: String?, val granularity: Granularity, val measure: Measure, val groupBy: GroupBy) data class GroupKey(val id: String, val label: String?, val color: ColorToken?) // label null: UI uses the default category name data class SpendBucket(val key: String, val start: String, val end: String, val totals: Map<String, Long>, val totalOre: Long) data class AnalyticsState(val filter: AnalyticsFilter, val start: String, val end: String, val groups: List<GroupKey>, val buckets: List<SpendBucket>, val byCategory: List<Pair<GroupKey, Long>>, val byAccount: List<Pair<GroupKey, Long>>, val totalOre: Long) // no error field: a CUSTOM filter with a missing date is resolved with today for that date; the S-11 range editor never sends one data class DrillDownState(val title: String, val totalOre: Long, val rows: List<LedgerRow.ExpenseRow>) // title: unlocalised parts joined by ", " (category custom name or default key, account name, bucket key); S-12 formats its visible title itself from the drillDown arguments interface AnalyticsRepository { fun analytics(filter: AnalyticsFilter): Flow<AnalyticsState> fun drillDown(filter: AnalyticsFilter, bucketKey: String?, categoryId: CategoryId?, accountId: AccountId?): Flow<DrillDownState> } // Insights (S-11, v0.31, D-141): model/Insights.kt; the server's E-34 trends and E-35 forecast, online only (§9.9), nothing stored. // Months "YYYY-MM" (Europe/Stockholm), amounts in öre for the requested measure, named after the E-34/E-35 fields (§14.5.7). data class TrendPoint(val month: String, val amountOre: Long, val movingAverageOre: Long) data class SpendTrend(val totalOre: Long, val averageOre: Long, val lastMonthOre: Long, val lastMonthVsAveragePct: Int?, val currentMonthOre: Long, val points: List<TrendPoint>) data class CategoryTrend(val categoryId: CategoryId, val category: Category?, val trend: SpendTrend) // category from Room, archived and deleted included; null when unknown data class SpendTrends(val measure: Measure, val today: String, val currentMonth: String, val months: Int, val household: SpendTrend, val categories: List<CategoryTrend>) // categories in the server's order data class ForecastMonth(val month: String, val recurringOre: Long, val baselineOre: Long, val forecastOre: Long) data class AccountForecast(val accountId: AccountId, val account: Account?, val currentMonthOre: Long, val months: List<ForecastMonth>) // account from Room, null when unknown data class SpendForecast(val measure: Measure, val today: String, val currentMonth: String, val accounts: List<AccountForecast>) // accounts in the server's order interface InsightsRepository { suspend fun trends(months: Int, measure: Measure): OnlineResult<SpendTrends> // months 1..24 suspend fun forecast(measure: Measure): OnlineResult<SpendForecast> } // Settings (S-13 to S-15, S-19 to S-22) interface ProfileRepository { fun household(): Flow<List<User>> suspend fun setDisplayName(name: String): OnlineResult<Unit> suspend fun setPicture(bytes: ByteArray, mimeType: String): OnlineResult<Unit> suspend fun removePicture(): OnlineResult<Unit> } interface CategoryRepository { fun all(): Flow<List<Category>> suspend fun create(name: String, icon: String, color: ColorToken): OnlineResult<CategoryId> suspend fun update(id: CategoryId, name: String?, icon: String, color: ColorToken): OnlineResult<Unit> // name null = reset default name suspend fun reorder(idsInOrder: List<CategoryId>): OnlineResult<Unit> suspend fun setArchived(id: CategoryId, archived: Boolean): OnlineResult<Unit> suspend fun delete(id: CategoryId): OnlineResult<Unit> fun deletable(id: CategoryId): Flow<Boolean> // v0.9, D-059: false for a default category or one used by a non-deleted expense or non-deleted recurring template (AC-7.6) } data class RecurringTemplate(val id: TemplateId, val draft: ExpenseDraft, val dayOfMonth: Int, val startPeriod: String, val endPeriod: String?, val paused: Boolean, val nextOccurrence: String?) data class NewRecurringTemplate(val draft: ExpenseDraft, val dayOfMonth: Int, val startPeriod: String, val endPeriod: String?, val paused: Boolean) // v0.13, D-091 interface RecurringRepository { fun all(): Flow<List<RecurringTemplate>> suspend fun create(t: NewRecurringTemplate): OnlineResult<TemplateId> // v0.13, D-091: the server mints the id suspend fun update(t: RecurringTemplate): OnlineResult<Unit> suspend fun delete(id: TemplateId): OnlineResult<Unit> } data class Device(val id: DeviceId, val user: User, val name: String, val pairedAt: String, val lastSeenAt: String, val appVersionCode: Int?, val appVersionName: String?, val current: Boolean, val revoked: Boolean) // appVersionName: v0.13, D-090 interface DeviceRepository { suspend fun list(): OnlineResult<List<Device>> suspend fun revoke(id: DeviceId): OnlineResult<Unit> } data class Invite(val id: InviteId, val kind: InviteKind, val targetUser: UserId?, val code: String?, val link: String?, val createdAt: String, val expiresAt: String) // code and link only right after creation interface InviteRepository { suspend fun list(): OnlineResult<List<Invite>> suspend fun create(kind: InviteKind, targetUser: UserId?): OnlineResult<Invite> suspend fun cancel(id: InviteId): OnlineResult<Unit> } data class Rejection(val mutationId: String, val entityType: EntityType, val entityId: String, val reason: SyncRejectionReason, val summary: String, val rejectedAt: String, val actor: User?, val lost: RejectedVersion?) // actor: v0.13, D-089; lost: v0.18, D-109 // D-109: the refused version as pushed (sync_rejections.rejected_payload), shown read-only on S-16; lost is null when the payload // cannot be decoded or its category or a user is missing on the phone. row is the ledger row it would have been (pending false); // for a settlement accountName, payer and mode are null and shares empty; notes is the expense's notes or the settlement's note. data class RejectedVersion(val row: LedgerRow, val accountName: String?, val payer: User?, val mode: SplitMode?, val shares: List<Share>, val notes: String, val deleted: Boolean) data class SyncStatusState(val summary: SyncSummary, val pending: List<LedgerRow>, val rejections: List<Rejection>) interface SyncRepository { fun status(): Flow<SyncStatusState> suspend fun syncNow() suspend fun dismiss(mutationId: String) } data class UpdateInfo(val versionCode: Int, val versionName: String, val sizeBytes: Long) sealed interface UpdateState { data object None : UpdateState data class Available(val info: UpdateInfo) : UpdateState data class Downloading(val info: UpdateInfo, val progress: Float) : UpdateState data class Failed(val info: UpdateInfo, val reason: UpdateFailure = UpdateFailure.Download) : UpdateState // reason: v0.32, D-155 data class NeedsInstallPermission(val info: UpdateInfo) : UpdateState } sealed interface UpdateFailure { // v0.32, D-155: why Failed; the downloaded file is deleted in every case data object Download : UpdateFailure // no answer, an error, or size or SHA-256 mismatch (AC-16.4) data object Blocked : UpdateFailure // STATUS_FAILURE_BLOCKED: the phone's security settings data class Install(val detail: String?) : UpdateFailure // any other installer failure; detail = the installer's status message } sealed interface UpdateCheck { // v0.13, D-092 data object UpToDate : UpdateCheck data class Available(val info: UpdateInfo) : UpdateCheck data object Failed : UpdateCheck } interface UpdateRepository { val state: Flow<UpdateState> suspend fun check(): UpdateCheck // v0.13, D-092 suspend fun checkNow(): UpdateCheck = check() // v0.30, D-140: S-22's button; skips the 6-hour throttle and restarts it suspend fun install() } data class AboutState(val versionName: String, val versionCode: Int, val serverUrl: String, val serverVersion: String?, val schemaVersion: Int?) // schemaVersion: v0.18, D-110 // D-110: serverVersion and schemaVersion from E-1 /health when S-22 opens online; offline or on failure serverVersion is the // X-Kvitt-Server-Version header of the last response and schemaVersion is null. // D-122: serverUrl is the paired server's base URL; while none is stored, AppBuildInfo.releaseServerUrl. interface AboutRepository { fun about(): Flow<AboutState> } // Not a :core:model type: defined in :data (di/DataModule.kt), provided by :app (di/AppBuildInfoModule.kt) from BuildConfig and // RELEASE_SERVER_URL = https://<kvitt.publicHost> (D-121, D-124), consumed by :data. data class AppBuildInfo(val versionCode: Int, val versionName: String, val debug: Boolean, val releaseServerUrl: String) // releaseServerUrl: v0.22, D-122 interface ConnectivityRepository { val online: Flow<Boolean> } // §9.9 // Push (§14.6), v0.13, D-095: model/Push.kt; :adapter:fcm maps FCM data messages into it data class PushEvent(val type: String, val entityType: String, val entityId: String, val actorUserId: String, val count: Int) Agents may add fields to these types only through a contract change (§14.8). A feature that needs a value not listed asks the orchestrator. Changes in v0.35 (D-169, D-170, D-173; card purchases, K2): a new file model/Cards.kt, and three members elsewhere. Names are binding; K2 may add fields only with a decision. // Card purchases (S-23 to S-27, FR-22, §9.12). Only the signed-in user's own card rows exist on the phone (D-161). @JvmInline value class CardConnectionId(val value: String) @JvmInline value class CardPurchaseId(val value: String) enum class CardConnectionStatus { ACTIVE, EXPIRED, DISCONNECTED } enum class CardPurchaseStatus { PENDING, BOOKED } enum class CardDirection { DEBIT, CREDIT } enum class CardFilter { TO_HANDLE, LINKED, IGNORED, ALL } enum class CardFetchError { BANK_UNAVAILABLE, RATE_LIMITED, CONSENT_EXPIRED, FAILED } // wire: lowercase; an unknown value reads as FAILED data class CardProvider(val id: String, val name: String, val issuer: String, val imageKey: String, val available: Boolean) // id and imageKey are open strings (CP-1) data class CardConnection(val id: CardConnectionId, val providerId: String, val status: CardConnectionStatus, val historyDays: Int, val validUntil: String?, val lastFetchAt: String?, val lastFetchError: CardFetchError?, val expiresSoon: Boolean) // expiresSoon: ACTIVE and validUntil within 14 days (CP-6), computed with the phone's clock data class LinkedExpense(val id: ExpenseId, val description: String, val accountName: String) data class CardPurchase(val id: CardPurchaseId, val connectionId: CardConnectionId, val status: CardPurchaseStatus, val direction: CardDirection, val date: String, val bookingDate: String?, val amountOre: Long?, val originalAmount: String?, val originalCurrency: String?, val merchant: String, val linked: LinkedExpense?, val ignored: Boolean, val pendingLocal: Boolean) // amountOre null: foreign currency (CP-7); linked null also while the expense is not on the phone data class ExpenseMatch(val id: ExpenseId, val description: String, val accountName: String, val payer: User, val date: String, val amountOre: Long) data class CardPurchaseRow(val purchase: CardPurchase, val matches: List<ExpenseMatch>) // matches (CP-10) only under TO_HANDLE, else empty data class CardDay(val date: String, val rows: List<CardPurchaseRow>) data class CardsState(val provider: CardProvider?, val connection: CardConnection?, val filter: CardFilter, val counts: Map<CardFilter, Int>, val days: List<CardDay>, val fetching: Boolean) // connection null: the empty state; fetching: an E-42 call of this phone is running data class CardPurchaseDetail(val row: CardPurchaseRow, val others: List<ExpenseMatch>) // others: "Välj en annan utgift" (CP-10) data class CardConnectStart(val attemptId: String, val authUrl: String, val expiresAt: String) sealed interface CardAttemptState { data object Pending : CardAttemptState data class Connected(val connection: CardConnection) : CardAttemptState data class Failed(val reason: String) : CardAttemptState // E-38 failure token, e.g. "no_account", "bank_error", "cancelled" data object Expired : CardAttemptState } interface CardRepository { val hasConnection: Flow<Boolean> // a connection with status ACTIVE or EXPIRED exists (S-5's "Från kortköp") fun cards(filter: CardFilter): Flow<CardsState> // S-23, from Room; works offline fun purchase(id: CardPurchaseId): Flow<CardPurchaseDetail?> // the sheet fun toHandle(): Flow<List<CardPurchase>> // S-27: debit, neither linked nor ignored, newest first fun purchaseForExpense(id: ExpenseId): Flow<CardPurchase?> // S-8's line suspend fun providers(): OnlineResult<List<CardProvider>> // E-36, online only (S-24) suspend fun startConnect(providerId: String, historyDays: Int): OnlineResult<CardConnectStart> // E-37, connect and renew suspend fun attempt(attemptId: String): OnlineResult<CardAttemptState> // E-38 suspend fun refresh(): OnlineResult<Unit> // E-42, then a card pull suspend fun setHistoryDays(id: CardConnectionId, days: Int): OnlineResult<Unit> // E-41, shorter only suspend fun disconnect(id: CardConnectionId, eraseHandled: Boolean): OnlineResult<Unit> // E-43 suspend fun prefill(id: CardPurchaseId, accountId: AccountId?): ExpenseDraft? // CP-9; accountId null: the AC-8.6 default; null when the purchase is unknown suspend fun link(id: CardPurchaseId, expenseId: ExpenseId) // local at once, sent later (CP-9); never fails suspend fun unlink(id: CardPurchaseId) suspend fun setIgnored(id: CardPurchaseId, ignored: Boolean) } Where it is used. :feature:cards (S-23 to S-27); :feature:expense (S-7 takes the optional navigation argument cardPurchaseId, starts from prefill and calls link after a successful save; S-8 reads purchaseForExpense and calls unlink); :feature:account (S-5 reads hasConnection for "Från kortköp"); :feature:settings (S-13 reads cards(CardFilter.ALL).connection for the "Anslut kort" subtitle, as built). :app binds CardRepository to :data's CardRepositoryImpl in DataBindingsModule, routes kvitt://cards/connected?attempt=<id> to S-25 (or S-23 when S-25 is not open), and adds the destination KvittDestination.Cards (§13.2). :data. DTOs for E-36 to E-44 with round-trip tests over K1's examples; CardRepositoryImpl on the Room tables of §14.2.1 and card_sync_state; the card cycle (push pending card rows with E-44, then pull E-40 until has_more is false) runs after every household sync cycle (§14.4.1) and after refresh; a 404 not_found from E-40 (a server before schema 4) is treated as "no card support" and leaves the tables empty; cursor_ahead or a household epoch change drops the card cache (pending rows kept) and pulls from 0. matches and others come from :domain's matchCardPurchase (§14.5.8) over Room's expenses. prefill applies CP-9 and the AC-8.6 default account; the editor runs the §9.11 suggestion itself as for any new expense. A local expense delete clears a local link to it (CP-9). The bank URL is opened by :feature:cards through a Custom Tab (androidx.browser, a catalog entry K2 adds). :core:fakes. FakeCardRepository with scenarios in fakes/cards/: no connection, first fetch, loaded (to handle, linked, ignored, credit, pending, foreign), empty filter, offline, expiring, expired, fetch failed, long content, attempt pending / connected / failed / expired; matches computed with :domain's function, as every fake computes derived values (§6.2). ExpenseDraft is unchanged: a prefilled draft is a draft with id null. Readings fixed in v0.39 (D-191 to D-196, as landed by K2 a8f91ee; no type changes: model/Cards.kt declares exactly the block above): The card cycle (D-191). :data's CardSync runs after each successful household cycle (SyncEngine) and after refresh, one at a time; its outcome never changes the household outcome or SyncSummary. A 404 from E-40 is "no card support": nothing is stored and the next cycle asks again. E-44 refusals and dead links (D-192, D-193). See §14.2.1: a refused change resets the row's card_version and moves the card cursor back before it; links to expenses no longer on the phone are cleared before E-44 and at every local delete or rejection that removes an expense. Catalogue cache (D-194). CardsState.provider comes from the last E-36 answer, cached in DataStore (card_providers, §14.2.2), so S-23, S-25 and S-26 name the card and draw its artwork offline; providers() stays online only and refreshes the cache; after a connect or an "Uppdatera" the phone asks E-36 when the cache is empty or lacks the connected provider. Following a fetch (D-195). After attempt returns Connected or E-42 answers fetching true, :data pulls E-40 every 3 s, at most 40 times, until the connection's last_fetch_at or last_fetch_error changes. refresh while this phone's E-42 call runs returns Ok without a request; CardsState.fetching is true for the duration of the call. Return link (D-196). :app parses kvitt://cards/connected?attempt=<id> (AppLink.CardConnected, the id 1 to 64 ASCII letters, digits or -); S-25, when open, polls that attempt at once; otherwise AppViewModel calls attempt once and opens S-23. CardPurchase.linked while the expense is missing (OQ-9). linked is null both when the purchase is unlinked and when it is linked to an expense not yet on the phone; the filters read the stored link, so such a purchase is listed under "Kopplade", without its "Kopplad till" line, and its sheet shows the to-handle actions until the expense arrives. A linkedExpenseId field would tell the two apart; it is a contract change (§14.8) and waits for the owner (§12 OQ-9). Readings fixed in v0.4 (no type changes): FieldError.error. Allowed values: a domain token of §14.5.3, required (a required value is missing or blank), or validation_failed (a §9.6 rule with no domain token: lengths, dates, day_of_month, periods). Analytics range errors. AnalyticsState has no error field. AnalyticsRepository.analytics never fails for a CUSTOM filter with customStart or customEnd null: it resolves the missing date as today. The S-11 custom-range editor does not let the user apply a range with a missing date, so this path is defensive only. resolveRange still throws IncompleteCustomRangeException (§14.5.4); the repository supplies today before calling it. DrillDownState.title. Stays a String. The repository fills it with the unlocalised parts as above, as the fakes do. S-12 does not display it as is: the feature formats the visible title ("Mat & hushåll, oktober 2026") from the arguments it passed to drillDown (the category or account, resolved through GroupKey with the default category name from resources, and the bucket key formatted with DateFormatter). Settlement rows in an account's list carry the allocation to that account (AC-11.7). Share names. se.hagstedt.kvitt.model.Share (a split share) and se.hagstedt.kvitt.model.analytics.AnalyticsMeasure.Share (the measure) share a simple name in different packages. Accepted; code that needs both imports one with an alias or qualifies it. Changes in v0.8 (D-049, D-054): Category suggestion types live in :domain, not here (§14.5.6); :core:model gains only ExpenseRepository.suggestCategory. Fourteen defaults. DefaultCategoryKey gains HOUSING, INSURANCE, CHILDREN, FEES (wire values housing, insurance, children, fees), ColorToken gains SLATE and AMBER, CategoryIcons.ALL gains key, shield, account_balance at the end. The localised default names are those of AC-7.2. ExpenseRepository.suggestCategory. Computed in :data from Room (every non-deleted expense on the phone, pending ones included, across all accounts and both users; and the active categories, neither archived nor deleted), the per-phone last-used category of the account (DataStore, §14.2.2) and the keyword table copied from contracts/category-keywords.csv at build time (D-055) and parsed with parseCategoryKeywords (D-056), by calling :domain's suggestCategory (§14.5.6). :data binds :domain's UnicodeText with java.text.Normalizer and Character, since :domain may not use java.* (§14.5.6). accountId null (no active account) gives the fallback other. The result is null while the phone holds no categories (before the first sync), and when other is archived and no active last-used category exists; the editor then shows no category until the user picks one (AC-8.6, v0.9). Stored expense_date values are valid ISO dates (§9.6), so parsing them for the history cannot fail. The editor (S-7) calls it on every change of the description and of the account while the category was not picked by hand (§9.11 CS-2, CS-3) and never when editing an existing expense (CS-1). ExpenseEditorOptions.defaultCategoryFor stays: it is the step-4 default before any description is typed. Changes in v0.9 (D-055 to D-057, D-059): Keyword table on the phone (D-055). :data and :core:fakes each copy contracts/category-keywords.csv at build time (tasks :data:copyCategoryKeywords and :core:fakes:copyCategoryKeywords, registered as an AGP generated resource directory); a missing file fails the build. It is packaged as the Java resource se/hagstedt/kvitt/data/category-keywords.csv (and se/hagstedt/kvitt/fakes/category-keywords.csv for the fakes, debug only). There is no committed copy. A :data test asserts byte identity with the contract file and the §14.8 rules. Enum declaration order (D-057). DefaultCategoryKey is declared in AC-7.2 sort order. The Rust wire enum, the OpenAPI DefaultCategoryKey enum and the 0002 CHECK list the ten v1 keys, then housing, insurance, children, fees. Wire values are unaffected (lowercase names; the OpenAPI equality test compares enums as sets). ExpenseEditorOptions.frequentCategoryIds (D-059). Per active account: the active (non-archived, non-deleted) categories ordered by the number of non-deleted expenses in that account that use them, descending; ties by sort_order ascending; at most 5 entries; categories with no use in the account are left out (the list may be shorter or empty). Counted over every expense in the phone's Room copy (both users, imported and recurring included), so both phones show the same order after sync; it is not a per-phone history like AC-8.6's "last used on this phone". The flow re-emits when expenses or categories change; the editor reads it once when it opens and on an account change, so tiles do not move while the user looks at them. UI rule (design, not contract): the row shows the account's list, filled up to five from the remaining active categories in sort_order; the selected category takes the fifth place when it is not among them. Fallback until M12d lands: the selected category first, then the first active categories in sort_order up to five. CategoryRepository.deletable(id) (D-059). Computed from Room: false for a default category (defaultKey != null) or one used by a non-deleted expense or non-deleted recurring template (AC-7.6). The server stays the authority: delete can still return Failed("category_is_default") or Failed("category_in_use") (for example when the partner's new expense has not synced yet), and the UI shows the same reason inline. The editor picks the text from deletable and defaultKey: default → settings_category_delete_blocked_default_short; in use and archived → settings_category_delete_blocked_in_use_archived; in use and active → settings_category_delete_blocked_in_use. Fallback until M12d lands: for a custom category "Ta bort kategori" is enabled and Failed("category_in_use") shows the in-use reason inline after the tap. Both members are implemented in :data and :core:fakes (every fake scenario computes them from its own data) by M12d. Readings fixed in v0.10 (D-060 to D-062, as landed by M12d 557af7e; no type changes): frequentCategoryIds holds only used categories (D-060). Each list holds only categories actually used in that account, so it may have fewer than five entries or be empty. Filling up to five from sort_order and placing the selected category fifth is the editor's job (UX-9, docs/ux/design-spec.md §3.7), not the repository's. frequentCategoryIds keys and ties (D-061). The map has a key for every active account (an empty list when nothing was used there) and no key for an archived account. Ties: use count descending, then sort_order ascending, then category id ascending, so Room and the fakes give the identical order. deletable edge cases (D-062). CategoryRepository.deletable(id) emits false for an unknown or already deleted id. Archived categories follow the same AC-7.6 rule as active ones. In :core:fakes, delete and deletable share one rule function, so a fake never offers a delete it then refuses. Changes in v0.30 and v0.31 (D-140, c0f4345; D-141, 1c9856b): UpdateRepository.checkNow() (D-140). S-22's "Check for update" calls it: it always asks E-5, whatever the 6-hour throttle of check() says, and restarts that window; the automatic checks on cold start and resume keep calling check(). The default implementation calls check(), so the fakes are unchanged; debug builds return UpToDate without a request (AC-16.5). Refines AC-16.2 and AC-16.6. InsightsRepository (D-141). trends(months: 1..24, measure), forecast(measure); online only (§9.9): Offline is returned without a request, Failed("network", null) when the server cannot be reached, else the §14.3.2 code. Category and account resolved from Room, archived and deleted rows included, null when unknown; nothing is stored. :data: api/AnalyticsDtos.kt, two KvittApi calls, repo/InsightsRepositoryImpl.kt (through the online gate), bound in DataModule; ExampleRoundTripTest round-trips the E-34 and E-35 examples. :core:fakes: FakeInsightsRepository, analytics/InsightsScenarios.kt, scenario flag insightsFailure. S-11's section and its rules: §13.3 S-11, D-142, D-143. Readings fixed in v0.11 (D-069, D-073 to D-075, as landed by M7a to M7f and M6b; no type changes): AnalyticsState.groups order (D-069). Unspecified; the UI does not rely on it. S-11 sorts legends and stacks itself: categories by sortOrder, accounts in AccountRepository.all() order. FieldError.field values (D-074). The model property names: amountOre, description, notes, date, split, accountId, categoryId, allocations, as :core:fakes and :data emit them. UpdateRepository.check() (D-073, revised by D-092 in v0.13). Returns nothing; S-22 reads UpdateState afterwards and treats a still-None state as "up to date". Returns an UpdateCheck since v0.13 (below). Quick row fill (D-075). The D-060 fill lives in :core:design's quickRowCategories(categories, frequent, selected); editors pass the raw frequentCategoryIds[accountId]. An empty or short list is filled from sort_order; the selected category takes the fifth place when absent. This replaces docs/ux/design-spec.md §3.7's interim "selected first, then sort_order" and the v0.9 fallback above. Changes in v0.13 (D-086 to D-095, as landed by M12e 8c60715): Pairing (D-086). SessionRepository.pair returns OnlineResult<Pairing(user, inviteKind)>, inviteKind read from the E-3 invite_kind; a wire value the app does not know is read as DEVICE, which leads to Home. S-1 goes to S-2 only for InviteKind.PARTNER. Fakes: FakeScenario.pairingInviteKind (null: partner for a member, admin_setup for the admin). Admin name from the invite link (D-087). Not a :core:model type: :feature:onboarding's InviteLink reads the optional from parameter of both link forms into PastedInvite.adminName, :app's AppLink.Invite(serverUrl, code, adminName) carries it to PairingScreen(initialAdminName) and PairingViewModel.prefill(serverUrl, code, adminName). A name that is not a §9.6 display name (1 to 40 code points after trimming, no control characters) or not valid percent-encoding is dropped. SyncSummary.lastAttemptFailed (D-088). True when the last finished cycle started (sync_state.last_attempt_at) after the last success (last_success_at), or none ever succeeded, and no cycle is running; false while one runs. Computed in :data's SyncSummaries (the two fixed-form timestamps compared as text); fakes take FakeScenario.lastAttemptFailed. SyncStatusPill, syncPillVariant and syncLineText dropped their failed parameter; S-16 shows "failed" when online and lastAttemptFailed. Rejection.actor (D-089). The user named by updated_by_user_id of the server's current row stored with the rejection (sync_rejections.server_current, §14.4.3), resolved to a household user; null when the server had no row or the user is unknown, and S-16's stale copy then names the partner. No protocol or Room change. Device.appVersionName (D-090). From the Device wire object's app_version_name (E-7, E-15, E-3); null until the device has sent X-Kvitt-App-Version-Name. :data sends the header on every call, the Coil picture requests included, with the BuildConfig versionName, omitted when it is blank, longer than 32 characters or not printable ASCII. NewRecurringTemplate (D-091). RecurringRepository.create takes the template fields without an id (E-28's body never had one); the server mints the id, which create returns; update keeps taking a RecurringTemplate. UpdateCheck (D-092, revising D-073). check() returns UpToDate (nothing newer published, a 404 from E-5 included, or within 6 hours of the last check that reached the server with nothing newer known), Available(info) or Failed (no answer or another error; state unchanged, and after no answer the next call tries again at once). Debug builds return UpToDate without a request (AC-16.5). SettleState.untouched (D-093). The accounts not in lines where the payer is owed (payerNetOre > 0), with nets that exclude the settlement being edited (AC-11.6), in AccountRepository.all() order; empty for a per-account settle-up. Computed in :data and in :core:fakes alike. Revises D-074's reading of Home balances. PushEvent (D-095). Lives in :core:model (model/Push.kt) as the project's own record; :adapter:fcm keeps PushListener and PushMapping, which maps the FCM data message into it. Pictures (v0.5 reading below) unchanged by assumption: no size parameter, E-11 always at 512. Readings fixed in v0.5 (no type changes): OnlineResult.Failed("network", null). A REST call that fails on the network (no answer from the server) returns code network, the one token outside §14.3.2, so the UI can show "Could not reach the server" (§9.9) rather than the Offline state, which means the call was not attempted (D-029). No "update required" state. HomeState has no field for a 426. After a 426 protocol_unsupported the phone stops syncing until the installed version code changes (§14.3.1, D-043); the update banner shows only when UpdateState.Available reports a newer published APK. Accepted. Pictures. :data always requests E-11 with size 512 and no size parameter is added to the UI contract: the owner confirmed on 2026-10-18 that the 128 size is not needed on the phone (the server keeps storing both, AC-4.4). Choices documented in :data and accepted: Rejection.summary (the rejected entity's own text) in android/data/src/main/kotlin/se/hagstedt/kvitt/data/repo/SettingsRepositories.kt; FieldChange display of splits, allocations and default category names in .../data/repo/Timeline.kt; RecurringTemplate.draft.date in .../data/repo/SettingsRepositories.kt (template mapping). 14.3 OpenAPI 3.1 outline Milestone M1 writes contracts/openapi.yaml (OpenAPI 3.1.0, info.title Kvitt, info.version 1, one server https://{host} (port 443, D-124; https://{host}:8443 in v0.22) with the server variable host, default kvitt.example.invalid (reserved by RFC 6761), description "the owner-chosen Kvitt host name, SPEC §10.5" (D-123; was https://icehack.asuscomm.com:8443; no operation changed), security scheme device = HTTP bearer) from this outline. This outline is binding; the YAML file must not add or drop anything. 14.3.1 Common rules Content type application/json; charset=utf-8 for every request and response body, except: PUT /me/picture (request image/jpeg, image/png or image/webp, raw bytes), GET /users/{user_id}/picture (response image/jpeg), GET /i/{code} and GET /cards/callback (response text/html; charset=utf-8), GET /apk/files/{file_name} (response application/vnd.android.package-archive). Request headers the app sends on every call: X-Kvitt-Protocol: 1, X-Kvitt-App-Version: <versionCode>, X-Kvitt-App-Version-Name: <versionName> (optional for the server; stored per device at E-3 and on the hourly last-seen update, §8.2; blank or longer than 32 characters is ignored; declared on every operation through CommonRules, D-090), Accept-Language: <device locale>, and Authorization: Bearer <token> on authenticated endpoints. A request to an authenticated endpoint without X-Kvitt-Protocol or with a value other than 1 gets 426 protocol_unsupported (the app then stops syncing until its installed version code changes, and shows the update banner when a newer APK is published, §14.2.4). The protocol check comes before the token check. X-Kvitt-App: <key> is a proxy-level header, not part of the API contract: the release app sends it on every request when built with kvitt.appKey, NPM's app gate checks it (§8.5, D-126), and the server neither reads nor declares it (contracts/openapi.yaml unchanged). Every response carries X-Kvitt-Server-Version: <crate version>. A known path with a method it does not support gets 405 with an empty body (no error code; the only error response without the JSON error shape), the X-Kvitt-Server-Version header included. An unknown path gets 404 not_found with the JSON error shape. Unknown JSON fields in requests are ignored. Missing required fields or wrong types: 400 invalid_request. Values outside §9.6: 422 validation_failed with field. The §9.6 value limits are not expressed as JSON Schema constraints in contracts/openapi.yaml; the schema fixes types only, and breaking a limit gives 422 validation_failed. Optional fields in responses are present with null, never omitted. (One exception: accepted and rejected results in the POST /sync response have different key sets, as the §14.4.3 example shows.) PATCH bodies: every field optional; absent = unchanged; at least one field required (invalid_request). Path ids that are not a UUID: 404 not_found. 14.3.2 Error shape and error codes { "code": "validation_failed", "message": "amount_ore must be between 1 and 1000000000", "field": "amount_ore" } message is English developer text and is never shown to users; the app maps code (and field) to localised strings. field is the JSON key concerned or null. Exhaustive list: code HTTP Meaning invalid_request 400 Malformed JSON, missing required field, wrong type, bad query parameter, empty PATCH invite_invalid 400 Invite code unknown, expired, used, cancelled or malformed unauthorized 401 Missing, malformed or unknown bearer token device_revoked 401 The token's device is revoked forbidden 403 Role does not allow the action (§8.4), or editing another user's profile not_found 404 Unknown or deleted id in the path; unknown APK file; no APK published; no picture household_full 409 Partner invite or accept when two users exist household_incomplete 409 Account, template, expense or settlement write before the partner joined name_taken 409 Account name already used by a non-deleted account account_not_empty 409 Account delete while referenced (AC-6.5) category_in_use 409 Category delete while referenced (AC-7.6) category_is_default 409 Delete of a default category, or name: null on a non-default category cannot_revoke_current_device 409 Revoke of the calling device no_accounts 409 Settlement proposal with no non-deleted accounts cursor_ahead 409 GET /sync with since greater than the server's current sequence value cards_unavailable 409 Card connection asked for while the server has no Enable Banking application for the caller (E-37, CP-13, D-175) card_consent_expired 409 Card refresh on an expired or disconnected connection (E-42, CP-6) expense_already_linked 409 The expense is already linked from another card purchase of the caller (E-44, CP-9) payload_too_large 413 Body over the limit of §8.6 unsupported_media_type 415 Picture with another content type validation_failed 422 A value breaks §9.6 or a split/settlement rule image_invalid 422 Picture cannot be decoded or exceeds 8000 × 8000 batch_too_large 422 Number of mutations in POST /sync outside 1 to 100 (D-036) protocol_unsupported 426 Missing or unsupported X-Kvitt-Protocol rate_limited 429 §8.6, with Retry-After internal 500 Unexpected server error (logged with a request id, returned in message) card_bank_unavailable 502 Enable Banking or the bank did not answer or refused (E-37; D-165) not_implemented 501 Route registered but not yet implemented (only during milestones M2a to M4); attached to no operation in contracts/openapi.yaml. No longer produced by the server since the server overhaul (6c405e1); it stays in the enum and the contract unavailable 503 Database busy beyond busy_timeout, or server shutting down Each endpoint below lists the codes it can return besides the always-possible unauthorized, device_revoked, protocol_unsupported, rate_limited, internal, unavailable (authenticated) or rate_limited, internal, unavailable (unauthenticated). 14.3.3 Wire objects All server-produced objects. ? marks nullable (always present). Types: string, int (64-bit), bool, ts (fixed RFC 3339), date (YYYY-MM-DD), period (YYYY-MM), uuid. // User { "id": uuid, "role": "admin" | "member", "display_name": string, "picture_version": int?, "created_at": ts, "updated_at": ts, "server_version": int } // Device (only in /me, /devices, /invites/accept) { "id": uuid, "user_id": uuid, "name": string, "app_version_code": int?, "app_version_name": string?, "created_at": ts, "last_seen_at": ts, "revoked_at": ts?, "is_current": bool } // Invite (code and link only in the POST /invites response; null in GET /invites) { "id": uuid, "kind": "admin_setup" | "partner" | "device", "target_user_id": uuid?, "code": string?, "link": string?, "created_at": ts, "expires_at": ts } // Share (of an account default) { "user_id": uuid, "share_bp": int } // Account { "id": uuid, "name": string, "default_shares": [Share, Share], "created_by_user_id": uuid, "created_at": ts, "updated_at": ts, "archived_at": ts?, "deleted_at": ts?, "server_version": int } // Category { "id": uuid, "default_key": "groceries" | "restaurants" | "housing" | "home" | "utilities" | "insurance" | "transport" | "travel" | "entertainment" | "health" | "children" | "shopping" | "fees" | "other" | null, "name": string?, "icon": string, "color": string, "sort_order": int, "created_at": ts, "updated_at": ts, "archived_at": ts?, "deleted_at": ts?, "server_version": int } // Split (of an expense): share_bp null for mode exact { "user_id": uuid, "share_ore": int, "share_bp": int? } // TemplateSplit: exactly one of share_bp / share_ore non-null; empty array for mode default { "user_id": uuid, "share_bp": int?, "share_ore": int? } // Expense { "id": uuid, "account_id": uuid, "category_id": uuid, "amount_ore": int, "description": string, "notes": string, "expense_date": date, "payer_user_id": uuid, "split_mode": "default" | "ratio" | "exact" | "full", "splits": [Split, Split], "recurring_template_id": uuid?, "recurring_period": period?, "created_by_user_id": uuid, "updated_by_user_id": uuid, "created_at": ts, "updated_at": ts, "deleted_at": ts?, "server_version": int } // Allocation { "account_id": uuid, "amount_ore": int } // Settlement { "id": uuid, "from_user_id": uuid, "to_user_id": uuid, "amount_ore": int, "settlement_date": date, "note": string, "allocations": [Allocation, ...], "created_by_user_id": uuid, "updated_by_user_id": uuid, "created_at": ts, "updated_at": ts, "deleted_at": ts?, "server_version": int } // RecurringTemplate { "id": uuid, "account_id": uuid, "category_id": uuid, "amount_ore": int, "description": string, "notes": string, "payer_user_id": uuid, "split_mode": "default" | "ratio" | "exact" | "full", "splits": [TemplateSplit, ...], "day_of_month": int, "start_period": period, "end_period": period?, "paused": bool, "last_generated_period": period?, "next_occurrence_date": date?, "created_by_user_id": uuid, "updated_by_user_id": uuid, "created_at": ts, "updated_at": ts, "deleted_at": ts?, "server_version": int } // AuditEntry { "id": uuid, "entity_type": "expense" | "settlement", "entity_id": uuid, "action": "create" | "update" | "delete", "source": "app" | "recurring" | "import", "actor_user_id": uuid, "client_at": ts, "server_at": ts, "changes": [ { "field": string, "old": any?, "new": any? }, ... ], "server_version": int } // Error { "code": string, "message": string, "field": string? } // CardProvider (E-36; D-160): an entry of the card catalogue; available = the server can connect it for the caller (CP-13) { "id": string, "name": string, "issuer": string, "image_key": string, "available": bool } // CardConnection (E-38, E-40, E-41, E-42; D-167). Only ever sent to its own user's devices. fetching: a fetch for it is // running at the time of the response. No session id, account uid or provider reference is ever sent. { "id": uuid, "provider_id": string, "status": "active" | "expired" | "disconnected", "history_days": int, "valid_until": ts?, "last_fetch_at": ts?, "last_fetch_error": "bank_unavailable" | "rate_limited" | "consent_expired" | "failed" | null, "fetching": bool, "created_at": ts, "updated_at": ts, "card_version": int } // CardPurchase (E-40, E-44; D-167, D-168). A tombstone has deleted_at set and its content erased (§14.1.3). { "id": uuid, "connection_id": uuid, "status": "pending" | "booked", "direction": "debit" | "credit", "purchase_date": date, "booking_date": date?, "amount_ore": int?, "original_amount": string?, "original_currency": string?, "merchant": string, "expense_id": uuid?, "ignored": bool, "created_at": ts, "updated_at": ts, "deleted_at": ts?, "card_version": int } // CardAttempt (E-37, E-38; D-162). auth_url only in the E-37 response (null in E-38); connection once connected. // failure stays a plain nullable string in the OpenAPI document, not an enum (D-187); its values are E-38's. { "id": uuid, "provider_id": string, "status": "pending" | "connected" | "failed" | "expired", "failure": string?, "auth_url": string?, "expires_at": ts, "connection": CardConnection? } Arrays splits are sorted by user_id, allocations by account_id, default_shares by user_id. 14.3.4 Endpoints E-1 GET /health (none). 200: { "status": "ok", "server_version": "0.1.0", "schema_version": 4, "db_ok": true } schema_version comes from a constant in the server code (the version its embedded migrations produce), not from the database, so /health answers with the database down. When the database check (SELECT 1) fails: 503 with the same shape, status "degraded", db_ok false. The OpenAPI document declares the 503 body as oneOf the health object or Error (an unavailable error from a shutting-down server is also possible). E-2 GET /setup/status (none). 200 { "initialized": bool }. initialized is true when a user with role admin exists (AC-1.5). E-3 POST /invites/accept (none). Request: { "code": "7K3MQX9D2HPA", "device_name": "Galaxy S26", "display_name": "Jacob" } display_name is optional in the schema; it is required for admin_setup and partner (invalid_request if missing), ignored for device. 200: { "token": "kvt_…", "invite_kind": "admin_setup" | "partner" | "device", "user": User, "device": Device, "household": [User, ...] } invite_kind is the kind of the accepted invite (D-086); the app shows S-2 only after partner (AC-2.10). The new device's app_version_code and app_version_name come from the request headers (§8.2). Errors: invalid_request, invite_invalid, household_full, validation_failed. E-4 GET /i/{code}?from=<name> (none). 200 HTML per AC-2.5, for any code string of 1 to 32 characters (validity is not checked). Otherwise 404 HTML, GET /i/ with an empty code included. The optional query parameter from (the inviting admin's display name, set by E-12's link) is percent-decoded (+ as space), trimmed and passed on only into the page's kvitt://invite?server&code&from link, never shown; a value that is not UTF-8, holds a control character or has more than 40 code points is dropped and the page still opens (D-087). E-5 GET /apk/latest (none). 200 latest.json content (§10.6). Errors: not_found (nothing published). E-6 GET /apk/files/{file_name} (none). 200 binary with Content-Length. Errors: not_found; 429 at 10 per minute per IP (§8.6). E-7 GET /me (device). 200: { "user": User, "device": Device, "household": [User, ...], "public_url": "https://<KVITT_PUBLIC_HOST>" } The example (contracts/examples/E-7-me/response.json) has "public_url": "https://kvitt.example.invalid" (D-123, D-124). E-8 PATCH /me (device). Request { "display_name": string }. 200 User. Errors: invalid_request, validation_failed. E-9 PUT /me/picture (device). Raw image body. 200 User (new picture_version). Errors: payload_too_large, unsupported_media_type, image_invalid. E-10 DELETE /me/picture (device). 200 User (picture_version null). Idempotent. Leaves the -removed marker of §10.4 so the next upload gets a new version (D-030). E-11 GET /users/{user_id}/picture?size=128|512&v=<picture_version> (device). 200 image/jpeg, ETag: "<picture_version>", Cache-Control: private, max-age=31536000, immutable. size defaults to 512; other values invalid_request. v is a cache key only and is ignored. Errors: not_found (unknown user or no picture), invalid_request. E-12 POST /invites (admin). Request { "kind": "partner" | "device", "target_user_id": uuid? } (target_user_id is optional and nullable in the schema, absent meaning null; it is required for device and must be null for partner). 201 Invite with code (12 characters, no hyphens) and link (<public_url>/i/<code>?from=<percent-encoded admin display name>, D-087; the app also reads links without from; the example's link is https://kvitt.example.invalid/i/4N8RVT2KW6ZC?from=Jacob, D-123, D-124). Errors: forbidden, invalid_request, household_full, not_found (target user). E-13 GET /invites (admin). 200 { "invites": [Invite, ...] } (pending only: not accepted, not cancelled, not expired; code and link null). Errors: forbidden. E-14 DELETE /invites/{invite_id} (admin). 204. Idempotent for already cancelled. An already accepted invite also answers 204 and nothing changes. Errors: forbidden, not_found. E-15 GET /devices (device). 200 { "devices": [Device, ...] } ordered by created_at, revoked included (with revoked_at). E-16 DELETE /devices/{device_id} (device). 204. Revoking an already revoked device is 204. Errors: not_found (an unknown id, or, for a member, a device of the other user: D-156, security review L-10), cannot_revoke_current_device. E-17 PUT /devices/current/push-token (device). Request { "fcm_token": string? } (the key is required, its value nullable; null clears). A string must be non-empty: "" is invalid_request (D-034); more than 512 characters after trimming is invalid_request with field fcm_token too (D-114, security review L-4). 204. Errors: invalid_request. E-18 POST /accounts (device). Request: { "name": "Vardag", "default_shares": [ { "user_id": "…", "share_bp": 5000 }, { "user_id": "…", "share_bp": 5000 } ] } 201 Account. Errors: invalid_request, validation_failed, name_taken, household_incomplete. E-19 PATCH /accounts/{account_id} (device). Request { "name"?: string, "default_shares"?: [Share, Share] }. 200 Account. Errors: invalid_request, validation_failed, name_taken, not_found. E-20 POST /accounts/{account_id}/archive, E-21 POST /accounts/{account_id}/unarchive (device). No body. 200 Account. Idempotent: in the state already held the row is returned unchanged with no new server_version (D-034). Errors: not_found. E-22 DELETE /accounts/{account_id} (device). 200 Account (tombstone). Errors: not_found, account_not_empty. E-23 POST /categories (device). Request { "name": string, "icon": string, "color": string }. 201 Category. Errors: invalid_request, validation_failed. E-24 PATCH /categories/{category_id} (device). Request { "name"?: string | null, "icon"?: string, "color"?: string, "sort_order"?: int } (name: null resets a default category's name). 200 Category. Reordering several categories is one PATCH per category whose sort_order changes. Errors: invalid_request, validation_failed, not_found, category_is_default. E-25 POST /categories/{category_id}/archive, E-26 POST /categories/{category_id}/unarchive (device). 200 Category. Idempotent as E-20 and E-21 (D-034). Errors: not_found. E-27 DELETE /categories/{category_id} (device). 200 Category (tombstone). Errors: not_found, category_in_use, category_is_default. E-28 POST /recurring-templates (device). Request: the RecurringTemplate fields account_id, category_id, amount_ore, description, notes, payer_user_id, split_mode, splits (TemplateSplit, rules of §9.1: none for default; two bp entries for ratio and full; two öre entries summing to the amount for exact), day_of_month, start_period, end_period, paused; no id: the server mints it and returns it in the 201 body (D-091). 201 RecurringTemplate. If a period is already due (§9.5), the server generates it before responding. Archived accounts and categories are accepted (AC-6.4). Errors: invalid_request, validation_failed (also for an unknown or deleted account_id or category_id, with field), household_incomplete. E-29 PATCH /recurring-templates/{template_id} (device). Any subset of the E-28 fields; split_mode and splits must be sent together. 200 RecurringTemplate. Errors: invalid_request, validation_failed, not_found. E-30 DELETE /recurring-templates/{template_id} (device). 200 RecurringTemplate (tombstone). Errors: not_found. E-31 GET /sync?since=<int>&limit=<int> (device). See §14.4.2. since is required (missing or negative: invalid_request); limit is optional. Errors: invalid_request, cursor_ahead. E-32 POST /sync (device). See §14.4.3. Errors (whole request): invalid_request, batch_too_large, payload_too_large, household_incomplete. E-33 POST /settlements/proposal (device). Request { "payer_user_id": uuid, "amount_ore": int, "exclude_settlement_id": uuid? } (exclude_settlement_id optional and nullable, absent meaning null). 200: { "allocations": [ { "account_id": "…", "amount_ore": 30000 } ], "excess_ore": 0, "over_settled_account_ids": [] } Computed with kvitt-domain::propose_allocation over the server's non-deleted rows. Errors: invalid_request, validation_failed, no_accounts. E-34 GET /analytics/trends?months=<int>&measure=<household|my_share> (device, read-only, D-133, D-138; operation getAnalyticsTrends). months 1 to 24, default 6; measure default household (AC-14.4). The two endpoints the D-134 brief named (averages, trends) are one. 200: { "measure": "household", "today": "2026-10-17", "current_month": "2026-10", "months": 3, "household": Trend, "categories": [ { "category_id": "…", "trend": Trend } ] } Trend = { "total_ore": int, "average_ore": int, "last_month_ore": int, "last_month_vs_average_pct": int?, "current_month_ore": int, "points": [ { "month": "YYYY-MM", "amount_ore": int, "moving_average_ore": int } ] }: points are the months whole months before the current one, oldest first; last_month_vs_average_pct is null when the average is 0. today is the Europe/Stockholm date, current_month its YYYY-MM. Rules §14.5.7. Errors: invalid_request with field months or measure. Unknown query keys are ignored; the last occurrence of a key wins. E-35 GET /analytics/forecast?measure=<household|my_share> (device, read-only, D-133, D-138; operation getAnalyticsForecast). months is not a parameter and is ignored like any unknown key. 200: { "measure": "household", "today": "2026-10-17", "current_month": "2026-10", "accounts": [ { "account_id": "…", "current_month_ore": 12000, "months": [ { "month": "2026-11", "recurring_ore": 4900, "baseline_ore": 40000, "forecast_ore": 44900 }, { "month": "2026-12", "recurring_ore": 0, "baseline_ore": 40000, "forecast_ore": 40000 } ] } ] } One entry per non-deleted account (archived included), ordered by created_at, then id; months are always the two calendar months after the current one; forecast_ore = recurring_ore + baseline_ore. Rules §14.5.7. Errors: invalid_request with field measure. Card purchases (E-36 to E-44, D-158 to D-170). Every authenticated card endpoint acts only on the caller's own user's rows (§8.4, CP-11): an id of the other user's connection, purchase or attempt is not_found. While the server has no card configuration at all, E-36 answers the catalogue with available false and the others behave as below. Rules in §9.12. E-36 GET /cards/providers (device). 200 { "providers": [CardProvider, ...] } in registry order (CP-1). Errors: none beyond the common ones. E-37 POST /cards/auth (device). Request { "provider_id": string, "history_days": int, "client": "android" | "web" }. Creates an attempt (CP-2) for a new connection or a renewal of the caller's existing one for that provider, calls Enable Banking POST /auth and answers 201 CardAttempt with auth_url and status pending. Errors: invalid_request, validation_failed (history_days, §9.6), not_found (unknown provider), cards_unavailable (no Enable Banking application for this user, CP-13), card_bank_unavailable (Enable Banking did not answer or refused, 502: when GET /aspsps or POST /auth fails, D-183; the OpenAPI document's BadGateway response). E-38 GET /cards/auth/{attempt_id} (device). 200 CardAttempt (auth_url null). A pending attempt past expires_at is answered and stored as expired. failure is one of cancelled (the bank redirected with an error, the user cancelled), no_account, bank_error (the session could not be created), state_invalid (never sent to a client: an unknown state names no attempt). Errors: not_found. E-39 GET /cards/callback?code=<code>&state=<state> (none; ?error=<error>&state=<state> when the user cancels). 200 text/html; charset=utf-8, the page of §13.3 "Card callback page", for success and failure alike (the status code does not tell an attacker whether a state existed); Cache-Control: no-store, Referrer-Policy: no-referrer. Never logged with its query (§8.7, §10.5.2). Not in contracts/openapi.yaml's JSON error shape: a malformed query also answers the failure page. Rate limit §8.6. The attempt rules (expired, used, no code and no error, the atomic claim, a session without accounts) are CP-2's (D-184). E-40 GET /cards/sync?since=<int>&limit=<int> (device). The caller's card rows with card_version > since, in one read transaction, like §14.4.2: 200 { "since": 0, "next_since": 41, "has_more": false, "server_time": "2026-10-24T12:00:00.000Z", "connections": [CardConnection], "purchases": [CardPurchase] } next_since is the highest card_version in the page, or since when empty; rows are counted together across both arrays, ordered by card_version, up to limit (default 500, max 1000); tombstones included. Errors: invalid_request, cursor_ahead (since greater than the current card_sequence value). E-41 PATCH /cards/connections/{connection_id} (device). Request { "history_days": int }, only a value ≤ the current one (CP-3; a longer one is a renewal through E-37). 200 CardConnection; the current value answers the unchanged connection with its existing card_version, no new version (D-187). Errors: invalid_request, validation_failed, not_found. E-42 POST /cards/connections/{connection_id}/refresh (device). No body. Fetches with the user present (CP-5), at most once per 60 seconds per connection; waits up to 25 seconds. 200 { "connection": CardConnection, "fetched": bool } (fetched false when the 60-second rule answered without contacting the bank, or the fetch is still running, then connection.fetching is true). A fetch that fails is recorded in last_fetch_error and still answers 200. Errors: not_found, card_consent_expired (status expired or disconnected, 409). E-43 DELETE /cards/connections/{connection_id}?erase_handled=<bool> (device). Disconnects (CP-12); erase_handled defaults to false. 200 CardConnection (status disconnected). Idempotent on a disconnected connection: no new version of it, but erase_handled=true still erases its linked and ignored purchases (D-187). Errors: invalid_request, not_found. E-44 PUT /cards/purchases/{purchase_id} (device). Request { "expense_id": uuid?, "ignored": bool } (both keys required). Sets the link and the ignore flag (CP-9); the rules of §9.6. A credit purchase can be neither linked nor ignored: validation_failed with field the key wrongly set (expense_id when it is not null, else ignored, D-187). 200 CardPurchase with a new card_version, or the unchanged row with its existing card_version when nothing changes (idempotent). Errors: invalid_request, validation_failed, not_found (the purchase, or with field expense_id an unknown or deleted expense), expense_already_linked (409, another purchase of the caller links that expense). 14.3.5 Examples as contract M1 writes one JSON example per request and response body above, plus one per error code, in contracts/examples/<E-id>-<name>/{request,response}.json and contracts/examples/errors/<code>.json, and the sync examples of §14.4. Directory names are E-<n>-<kebab-name> (for example E-1-health, E-32-sync-push). The server's tests serialise its responses for the same fixtures and compare; the app's :data tests decode every example into its DTOs and re-encode it, comparing JSON values. The server's test harnesses seed the two users after the fourteen category seeds, so the users have server_version 15 and 16; E-7-me/response.json shows those values and its test compares them (D-058). E-34 and E-35 have response examples only (E-34-analytics-trends/response.json, E-35-analytics-forecast/response.json, v0.29, D-138); tools/contracts-check.py checks that the operations are exactly E-1 to E-35 (136 checks at 50a0d67); since v0.35 E-1 to E-44 (K1; 157 checks at 671c00d, 17 of them match_card_purchase cases), with request and response examples for E-36 to E-38 and E-40 to E-44 (E-36-card-providers, E-37-card-auth, E-38-card-attempt, E-40-card-sync, E-41-card-connection-update, E-42-card-refresh, E-43-card-disconnect, E-44-card-purchase-update) and one per new error code. E-39 returns HTML like E-4: it is in contracts/openapi.yaml with a text/html response and has no JSON example. 14.4 Sync protocol v1 14.4.1 Principles The server is the authority. The phone keeps a full copy and a cursor. Every synced row carries server_version from one global sequence (§14.1). The cursor is the highest server_version the phone has applied. Phones push only expenses and settlements. Everything else changes through REST and comes back through pull (the REST response is also written locally at once). Card connections and purchases (D-161) are not part of this protocol: they are the holder's private rows with their own cursor (card_version, E-40) and their own writes (E-44); X-Kvitt-Protocol stays 1. The phone runs its card cycle after each household cycle (§14.2.4). Conflict rule: per row, last write wins on the client updated_at; ties go to the server's copy; deletes are final and always win. Pushes are idempotent per mutation_id. Tombstones are kept forever on both sides and are synced like any other row. A sync cycle is: push all pending rows (in batches), then pull until has_more is false. One cycle at a time per process (a Mutex in the sync engine; WorkManager unique work names kvitt-sync for one-off work, policy APPEND_OR_REPLACE, and kvitt-sync-periodic for the periodic work, policy KEEP; WorkManager cannot share one unique name between periodic and one-off work, D-028). Triggers in AC-15.3; pushes go in batches of 100, pulls in pages of 500. 14.4.2 Pull: GET /sync?since=N&limit=L Server, in one read transaction per page (so the cursor check and the page see one snapshot): N missing or negative, or L outside 1 to 1000: 400 invalid_request. If N > current sync_sequence.value: 409 cursor_ahead. Select the L (default 500, max 1000) rows with the lowest server_version > N across users, categories, accounts, recurring_templates, expenses, settlements, audit_log (a UNION ALL of (server_version, table, id) ordered by server_version), including tombstones. An expense with its splits, a settlement with its allocations, an account with its default shares and a template with its splits each count as one row. Respond 200: { "epoch": "30b85fb529aac0016dc91650841005b9", "since": 0, "next_since": 512, "has_more": true, "server_time": "2026-10-17T12:00:00.000Z", "users": [User], "categories": [Category], "accounts": [Account], "recurring_templates": [RecurringTemplate], "expenses": [Expense], "settlements": [Settlement], "audit_entries": [AuditEntry] } next_since is the highest server_version in the page, or N when the page is empty. has_more is true when rows with server_version > next_since exist. Every array is present (possibly empty) and sorted by server_version. Phone, per page, in one Room transaction: If sync_state.epoch is non-null and differs from epoch: discard the page and run epoch recovery (§14.4.8). Apply arrays in this order: users, categories, accounts, recurring_templates, expenses, settlements, audit_entries. For each row: if the local row exists and has server_version ≥ the incoming one, skip. For expenses and settlements: if the local row is pending, skip (the push will resolve it). Otherwise upsert the row, replace its child rows, set local_updated_at. Audit entries are insert-or-ignore. Set sync_state.cursor = next_since, sync_state.epoch = epoch. Repeat while has_more. Then set last_success_at. A 409 cursor_ahead answer to a pull is treated as epoch recovery (§14.4.8): cursor 0, epoch cleared, every local expense and settlement marked pending with a new pending_mutation_id, and the cycle restarted (D-026). 14.4.3 Push: POST /sync Request (1 to 100 mutations, body ≤ 1 MiB): { "mutations": [ { "mutation_id": "01929c5e-6c1f-7d3a-9b2e-4f5a6b7c8d9e", "entity_type": "expense", "entity": { "id": "01929c5e-1111-7aaa-8bbb-000000000001", "account_id": "…", "category_id": "…", "amount_ore": 41200, "description": "ICA Maxi", "notes": "", "expense_date": "2026-10-16", "payer_user_id": "…", "split_mode": "default", "splits": [ { "user_id": "…", "share_ore": 20600, "share_bp": 5000 }, { "user_id": "…", "share_ore": 20600, "share_bp": 5000 } ], "created_at": "2026-10-16T17:02:11.123Z", "updated_at": "2026-10-16T17:02:11.123Z", "deleted_at": null } }, { "mutation_id": "…", "entity_type": "settlement", "entity": { "id": "…", "from_user_id": "…", "to_user_id": "…", "amount_ore": 50000, "settlement_date": "2026-10-16", "note": "", "allocations": [ { "account_id": "…", "amount_ore": 50000 } ], "created_at": "…", "updated_at": "…", "deleted_at": null } } ] } The pushed entity contains exactly the client-writable fields: for expenses id, account_id, category_id, amount_ore, description, notes, expense_date, payer_user_id, split_mode, splits, created_at, updated_at, deleted_at; for settlements id, from_user_id, to_user_id, amount_ore, settlement_date, note, allocations, created_at, updated_at, deleted_at. Server-owned fields (server_version, created_by_user_id, updated_by_user_id, recurring_template_id, recurring_period) are ignored if sent. A delete is the full entity with deleted_at set. Every pushed id (mutation_id, entity.id and every id inside the entity) must be a UUID in the canonical form of the conventions (lowercase, hyphenated, 36 characters); another spelling of a valid UUID is not accepted (D-037). Response 200, one result per mutation in request order: { "server_time": "2026-10-17T12:00:00.000Z", "results": [ { "mutation_id": "…", "entity_type": "expense", "entity_id": "…", "status": "accepted", "server_version": 913, "entity": Expense }, { "mutation_id": "…", "entity_type": "settlement", "entity_id": "…", "status": "rejected", "reason": "stale", "message": "a newer version exists", "current": Settlement } ] } entity and current are full wire objects (§14.3.3) or, for current, null when the server has no row with that id. Accepted and rejected results have different key sets exactly as in the example (accepted: mutation_id, entity_type, entity_id, status, server_version, entity; rejected: mutation_id, entity_type, entity_id, status, reason, message, current); this overrides the "present with null" rule of §14.3.1 for these objects. server_version is the row's version after processing. 14.4.4 Server processing of one mutation The whole request runs in one BEGIN IMMEDIATE transaction; each mutation in its own SAVEPOINT, rolled back on rejection. Pushes are enqueued after commit. Before the transaction, the whole request is checked: 0 or more than 100 mutations is 422 batch_too_large (D-036); a mutation whose mutation_id or entity.id is not a canonical UUID, or whose entity_type is not expense or settlement, makes the whole request fail with 400 invalid_request (without these keys no per-mutation result can be formed, D-035). Steps, in order: Replay. If mutation_id exists in sync_mutations, return the stored result unchanged (no other effect). Household. Fewer than two users: the whole request fails with 409 household_incomplete before any mutation. Shape. Every other shape error (missing fields, wrong types, unknown enum values, ids that are not canonical UUIDs, timestamps not in the fixed form): rejected, validation_failed, per mutation (D-035). Clock. updated_at > server now + 10 minutes: rejected, clock_skew. Load the stored row by id. Stored row is a tombstone. If the pushed entity is also a delete: accepted, no change, no audit, no push (idempotent delete). Otherwise rejected, deleted, current = the tombstone. Pushed entity is a delete (deleted_at non-null): Stored row exists: set deleted_at = pushed deleted_at, updated_at = the later of stored and pushed updated_at, keep every other stored field, updated_by_* from the caller, new server_version, audit delete with changes [{"field":"deleted_at","old":null,"new":<deleted_at>}], push *_deleted. accepted. This applies even when the pushed updated_at is older (deletes always win). For an expense, in the same savepoint, every non-deleted card purchase linked to it gets expense_id null, updated_at = server now and a new card_version (CP-9, D-169), so its holder sees it under "Att hantera" again; nothing about it is audited or pushed. No stored row (created and deleted before it ever synced): run the full validation of step 8 (field rules, domain rules and references), so the tombstone satisfies the schema; on failure rejected as in step 8. Otherwise insert the row as a tombstone with a new server_version, no audit, no push. accepted (D-037). Validate, in this order: the field rules of §9.6, then the domain rules of §9.1 (expenses) or §9.4 settlement validity (settlements), then references: account_id, every allocation account_id, category_id must exist and not be deleted (reference_not_found otherwise; archived is fine); user ids must be household users (validation_failed). Failure: rejected with that reason, current = stored row or null. No stored row: insert with created_by_user_id = updated_by_user_id = caller's user, updated_by_device_id = caller's device, server_received_at = now, new server_version; audit create with every diff field (old null); push *_created. accepted. Stored row exists, pushed updated_at ≤ stored updated_at: rejected, stale, current = stored row. Stored row exists, newer: compute the diff (§14.4.7). Empty diff: change nothing (not even updated_at), no audit, no push, accepted with the stored row and its existing server_version. Otherwise update fields and children, updated_by_* from the caller, new server_version, audit update with the diff, push *_updated. accepted. recurring_template_id, recurring_period, created_by_user_id and created_at keep their stored values (a pushed created_at is ignored on update, D-037). Store (mutation_id, device_id, entity_type, entity_id, result JSON, now) in sync_mutations, for accepted and rejected results alike (step 1 then replays it). Every rejection, at steps 3 and 4 too, carries current = the stored row with that id, or null when there is none (D-037). 14.4.5 Phone push procedure Read pending expenses and settlements ordered by local_updated_at ascending; take up to 100. Build each mutation from the row with mutation_id = pending_mutation_id. POST /sync. On a network error or 5xx: stop the cycle, keep everything pending, let WorkManager retry with exponential backoff starting at 30 seconds. On 401 device_revoked: AC-3.3. On 401 unauthorized: SessionState.Unrecognised (§14.4.8). On 429: retry as for 5xx. On 426: stop syncing until the installed version code changes (§14.3.1). A push refused as a whole (400 invalid_request, 413 payload_too_large, 409 household_incomplete, 422 batch_too_large) counts as a batch with no progress: the cycle goes on to pull and records the code in sync_state.last_error_code (D-040). Apply results in one Room transaction: accepted: if the row's pending_mutation_id still equals the sent mutation_id, overwrite the local row with entity, set pending = false, pending_mutation_id = null. If it differs (edited again during the request), set only server_version, created_by_user_id, updated_by_user_id from entity and leave it pending. rejected with current equal to the pushed entity in every client-writable field: treat as accepted with current (no rejection record). This covers re-pushes of an already stored state. other rejected: if pending_mutation_id still matches, overwrite the local row with current (or delete the local row and its children if current is null), set pending = false, and insert a sync_rejections row with the pushed entity as rejected_payload. If it no longer matches, insert the rejection record only and leave the newer local edit pending. Reason clock_skew: do not overwrite and do not clear pending; give the row a new pending_mutation_id (the server stored the rejection under the old one and would replay it), set sync_state.clock_skew = true and stop the cycle (D-027). Re-stamp (D-094, revising D-027 as implemented by M12e): when sync_state.clock_skew is set at the start of a cycle, every pending expense and settlement whose updated_at is later than the phone's clock now gets updated_at = now (and a tombstone's deleted_at too, when it is later than now), in one Room transaction before pushing; rows stamped no later than now are untouched, so a row stamped by a clock that is still ahead is refused again until the clock is fixed, and a corrected clock heals it. Room schema unchanged. Repeat until no pending rows remain or a batch made no progress, then pull. 14.4.6 Rejection reasons reason (exhaustive) When Phone's user-facing explanation (S-16) stale Someone saved a newer version first "Your change was replaced by a newer change from "; is Rejection.actor, the updated_by_user_id of the stored current (sync_rejections.server_current), the partner when unknown (D-089) deleted The row was deleted "This was deleted before your change arrived" validation_failed The row breaks a rule (should not happen with a correct phone) "This change was not valid and was not saved" reference_not_found Its account or category was deleted "Its account or category no longer exists" clock_skew Phone clock more than 10 minutes ahead "Your phone's clock is wrong. Fix it and sync again" For every reason S-16 can show what was lost: Rejection.lost is decoded from sync_rejections.rejected_payload and shown read-only (§13.3 S-16, D-109). 14.4.7 Audit diff Diff fields and their JSON value types: Entity Field Value expense account_id, category_id, payer_user_id string (uuid) expense amount_ore int expense description, notes string expense expense_date string (date) expense split_mode string (enum) expense splits array of Split sorted by user_id settlement from_user_id, to_user_id string (uuid) settlement amount_ore int settlement settlement_date string (date) settlement note string settlement allocations array of Allocation sorted by account_id both (delete only) deleted_at string (ts) create: one change per field above except deleted_at, old null, in the table's order. update: one change per field whose JSON value differs, in the table's order. delete: exactly the deleted_at change. client_at = the pushed updated_at (for delete, the pushed deleted_at); server_at = server now. Scheduler and importer use server now for both. The phone renders changes with ids resolved to names (FR-12). 14.4.8 Epoch recovery and re-pairing sync_epoch changes only when the owner runs rotate-epoch after a restore (§10.9). When a pull returns a different epoch, the phone, in one transaction: sets cursor = 0, stores the new epoch, and marks every local expense and settlement (tombstones included) pending with a new pending_mutation_id, keeping updated_at. It then runs a normal cycle: push everything (rows the restored server lacks are inserted, rows it has with older updated_at are updated, identical rows come back as stale with equal content and are silently accepted per §14.4.5), then a full pull. Devices paired after the restored backup do not exist on the restored server; their requests get 401 unauthorized. The app keeps its local data and shows S-1 with "Pair this phone again". After pairing with a new invite: if the user id equals the previous one, the local data is kept and the epoch-recovery push runs; otherwise local data is wiped first. 14.4.9 Limits and timing Item Value Mutations per push 100 Rows per pull page default 500, max 1000 Debounce after a local write 2 seconds Periodic background sync 15 minutes (WorkManager minimum), requires a connected network FCM-triggered sync expedited one-off work Retry backoff exponential from 30 seconds (WorkManager) sync_mutations retention 90 days, pruned daily at 04:00 Europe/Stockholm; rows with received_at strictly older than 90 days are deleted (D-021, D-039) Tombstone retention forever Token lifetime until revoked Notification sync wait (AC-13.5) 20 seconds With these values a phone offline for 14 days loses nothing: tokens do not expire, cursors stay valid (versions only grow), and idempotency records outlive any realistic retry. 14.5 Domain rules as pure functions Implemented twice: Kotlin in :domain (package se.hagstedt.kvitt.domain, input and output types in :core:model package se.hagstedt.kvitt.model.money) and Rust in kvitt-domain. Both are pure (no I/O, no clock, no randomness, no locale) and must pass every vector in contracts/test-vectors/. Analytics and the category suggestion (§14.5.6) exist only in Kotlin; next_occurrence_date and the day clamping exist only in Rust (D-015). The rules themselves are §9.1, §9.3 and §9.4; this section fixes signatures, error tokens and the vector format. 14.5.1 Types Ids are plain strings in domain inputs (the vectors use short ids like "a", "b", "x"; implementations must not assume UUID format). Money is Long / i64 öre; bp is Int / u32. Because bp is u32 in Rust, negative bp is unrepresentable there and the vectors contain none; bp_out_of_range means a value above 10000. All domain functions, analytics included, receive only non-deleted rows; excluding tombstones is the caller's job and is tested in :data and the server, not in the vectors. Kotlin (:core:model, package se.hagstedt.kvitt.model.money): sealed interface SplitSpec { data class Ratio(val bp: Map<String, Int>) : SplitSpec // modes default and ratio data class Exact(val ore: Map<String, Long>) : SplitSpec // mode exact data class Full(val bearerUserId: String) : SplitSpec // mode full } enum class SplitError { AMOUNT_OUT_OF_RANGE, USERS_INVALID, PAYER_UNKNOWN, BP_OUT_OF_RANGE, BP_SUM_NOT_10000, EXACT_NEGATIVE, EXACT_SUM_MISMATCH, BEARER_UNKNOWN, SHARE_USERS_MISMATCH } sealed interface SplitResult { data class Ok(val shares: Map<String, Long>) : SplitResult data class Err(val error: SplitError) : SplitResult } data class BalanceExpense(val accountId: String, val amountOre: Long, val payerUserId: String, val shares: Map<String, Long>) data class BalanceSettlement(val fromUserId: String, val toUserId: String, val allocations: Map<String, Long>) // accountId -> öre data class Balances(val perAccount: Map<String, Map<String, Long>>, val global: Map<String, Long>) // accountId -> userId -> net data class AccountPosition(val accountId: String, val createdAt: String, val archived: Boolean, val payerNetOre: Long) enum class AllocationError { AMOUNT_OUT_OF_RANGE, NO_ACCOUNTS } data class Allocation(val accountId: String, val amountOre: Long) sealed interface AllocationResult { data class Ok(val allocations: List<Allocation>, val excessOre: Long, val overSettledAccountIds: List<String>) : AllocationResult data class Err(val error: AllocationError) : AllocationResult } enum class SettlementError { AMOUNT_OUT_OF_RANGE, SAME_USER, USER_UNKNOWN, NO_ALLOCATIONS, TOO_MANY_ALLOCATIONS, ALLOCATION_NOT_POSITIVE, DUPLICATE_ACCOUNT, ALLOCATION_SUM_MISMATCH } Rust (kvitt-domain): pub enum SplitSpec { Ratio { bp: BTreeMap<String, u32> }, Exact { ore: BTreeMap<String, i64> }, Full { bearer_user_id: String } } #[derive(Debug, Clone, Copy, PartialEq, Eq, Serialize, Deserialize)] #[serde(rename_all = "snake_case")] pub enum SplitError { AmountOutOfRange, UsersInvalid, PayerUnknown, BpOutOfRange, #[serde(rename = "bp_sum_not_10000")] BpSumNot10000, // rename_all alone gives "bp_sum_not10000" (D-006) ExactNegative, ExactSumMismatch, BearerUnknown, ShareUsersMismatch } pub struct BalanceExpense { pub account_id: String, pub amount_ore: i64, pub payer_user_id: String, pub shares: BTreeMap<String, i64> } pub struct BalanceSettlement { pub from_user_id: String, pub to_user_id: String, pub allocations: BTreeMap<String, i64> } pub struct Balances { pub per_account: BTreeMap<String, BTreeMap<String, i64>>, pub global: BTreeMap<String, i64> } pub struct AccountPosition { pub account_id: String, pub created_at: String, pub archived: bool, pub payer_net_ore: i64 } pub enum AllocationError { AmountOutOfRange, NoAccounts } pub struct Allocation { pub account_id: String, pub amount_ore: i64 } pub struct AllocationProposal { pub allocations: Vec<Allocation>, pub excess_ore: i64, pub over_settled_account_ids: Vec<String> } pub enum SettlementError { AmountOutOfRange, SameUser, UserUnknown, NoAllocations, TooManyAllocations, AllocationNotPositive, DuplicateAccount, AllocationSumMismatch } 14.5.2 Functions Function Kotlin Rust Split fun computeSplit(amountOre: Long, payerUserId: String, userIds: List<String>, spec: SplitSpec): SplitResult pub fn compute_split(amount_ore: i64, payer_user_id: &str, user_ids: &[String], spec: &SplitSpec) -> Result<BTreeMap<String, i64>, SplitError> Balances fun computeBalances(userIds: List<String>, accountIds: List<String>, expenses: List<BalanceExpense>, settlements: List<BalanceSettlement>): Balances pub fn compute_balances(user_ids: &[String], account_ids: &[String], expenses: &[BalanceExpense], settlements: &[BalanceSettlement]) -> Balances Proposal fun proposeAllocation(amountOre: Long, accounts: List<AccountPosition>): AllocationResult pub fn propose_allocation(amount_ore: i64, accounts: &[AccountPosition]) -> Result<AllocationProposal, AllocationError> Settlement check fun validateSettlement(amountOre: Long, fromUserId: String, toUserId: String, userIds: List<String>, allocations: List<Allocation>): SettlementError? pub fn validate_settlement(amount_ore: i64, from_user_id: &str, to_user_id: &str, user_ids: &[String], allocations: &[Allocation]) -> Result<(), SettlementError> Over-settle warnings fun overSettledAccounts(allocations: List<Allocation>, accounts: List<AccountPosition>): List<String> pub fn over_settled_accounts(allocations: &[Allocation], accounts: &[AccountPosition]) -> Vec<String> Recurring dates (D-015) none next_occurrence_date and the clamped occurrence date of a period (module recurring.rs); M2a fixes the exact signatures and lists them in its report Semantics beyond §9: computeSplit: userIds must have exactly 2 distinct entries (users_invalid); payerUserId must be one of them (payer_unknown); the Ratio/Exact map keys must equal userIds as a set (share_users_mismatch); Full.bearerUserId must be one of them (bearer_unknown); amount outside 1 to 1 000 000 000 is amount_out_of_range. Errors are checked in the order of the SplitError enum and the first failure is returned. The result map has both user ids. Full is computed as Ratio with bearer 10000 (so payer remainder rules apply trivially). computeBalances: inputs contain only non-deleted rows. perAccount has an entry for every id in accountIds (zeros included) and for any other account id referenced; each inner map has every id of userIds. global sums perAccount. Expenses' and settlements' account ids not in accountIds still count. proposeAllocation: amountOre outside 1 to 1 000 000 000 (§9.6) is amount_out_of_range. accounts are all non-deleted accounts with the payer's net per account (callers compute nets with computeBalances, excluding the settlement being edited). Errors in enum order. Allocations are in the order produced by §9.4. overSettledAccountIds lists the account that received excessOre (empty when excessOre is 0). validateSettlement: errors in enum order; null / Ok(()) when valid. Reference existence is not checked here (the server checks it, §14.4.4). overSettledAccounts: ids, in allocation order, whose allocation exceeds max(0, −payerNetOre); an allocation for an account not in accounts counts as net 0. Recurring dates (Rust only): the clamped date of period YYYY-MM for day_of_month 1 to 31 is that day, or the last day of the month when the month is shorter (§9.5, AC-9.2). next_occurrence_date takes the template's day_of_month, start_period, end_period, last_generated_period, paused and deleted state and returns the date defined in §9.5 (null when paused, deleted or past end_period). Pure: no clock, no time zone. No vector file covers them; M2a's unit tests cover every clamping case of AC-9.2 and the null cases. 14.5.3 Error tokens on the wire and in vectors Snake-case of the enum names: amount_out_of_range, users_invalid, payer_unknown, bp_out_of_range, bp_sum_not_10000, exact_negative, exact_sum_mismatch, bearer_unknown, share_users_mismatch, no_accounts, same_user, user_unknown, no_allocations, too_many_allocations, allocation_not_positive, duplicate_account, allocation_sum_mismatch. The server puts the token in the message of validation_failed errors and rejections; the phone uses it as FieldError.error. The token for a wrong bp sum is exactly bp_sum_not_10000 on both sides (D-006): the Rust variant carries an explicit #[serde(rename = "bp_sum_not_10000")], and the Kotlin side must emit the same string (the lowercase of BP_SUM_NOT_10000), never a token derived by a generic camel-to-snake conversion. 14.5.4 Analytics (Kotlin only) Types in :core:model, package se.hagstedt.kvitt.model.analytics (D-017); functions in :domain. data class AnalyticsExpense(val date: LocalDate, val accountId: String, val categoryId: String, val amountOre: Long, val shares: Map<String, Long>) data class DateRange(val start: LocalDate, val endInclusive: LocalDate) enum class AnalyticsGranularity { MONTH, WEEK } sealed interface AnalyticsMeasure { data object Household : AnalyticsMeasure; data class Share(val userId: String) : AnalyticsMeasure } enum class AnalyticsGroupBy { CATEGORY, ACCOUNT } data class Bucket(val key: String, val start: LocalDate, val endInclusive: LocalDate, val totals: Map<String, Long>, val total: Long) data class SpendSeries(val buckets: List<Bucket>, val groupTotals: Map<String, Long>, val grandTotal: Long) fun spendSeries(expenses: List<AnalyticsExpense>, range: DateRange, granularity: AnalyticsGranularity, measure: AnalyticsMeasure, groupBy: AnalyticsGroupBy): SpendSeries fun resolveRange(preset: RangePreset, today: LocalDate, earliestExpense: LocalDate?, customStart: LocalDate?, customEnd: LocalDate?): DateRange (LocalDate is kotlinx.datetime.LocalDate. AnalyticsMeasure.Share and se.hagstedt.kvitt.model.Share share a simple name; accepted, §14.2.4.) spendSeries: expenses outside the range are ignored. Buckets cover the range completely, in order, including empty ones. Month keys YYYY-MM, week keys YYYY-Www (ISO week-numbering year, week 1 contains the first Thursday). A bucket's start/endInclusive are clipped to the range. totals maps group id (category id or account id) to öre, omitting zero groups; total is their sum. Measure Household adds amountOre; Share(u) adds shares[u] (0 if absent). groupTotals sums over all buckets, omitting zeros. resolveRange: THIS_MONTH = first of the current month to today; LAST_3_MONTHS, LAST_6_MONTHS, LAST_12_MONTHS = first day of the month N−1 months before the current month to today; THIS_YEAR = 1 January to today; ALL_TIME = earliestExpense (or today when null) to today; CUSTOM = the custom dates, swapped if start > end. Expenses dated after today are therefore excluded from presets; a custom range may include future dates. CUSTOM with a null customStart or customEnd throws IncompleteCustomRangeException, a subclass of IllegalArgumentException declared in :domain (D-011); the caller (the AnalyticsRepository implementation in :data, and its fake) catches it and maps it to validation_failed (D-018; no vector covers it; in practice the repository resolves a missing custom date as today before calling, §14.2.4); ALL_TIME with earliestExpense after today gives the range today..today. 14.5.5 Test-vector format One file per function in contracts/test-vectors/: compute_split.json, compute_balances.json, propose_allocation.json, validate_settlement.json, over_settled_accounts.json, spend_series.json (Kotlin only), resolve_range.json (Kotlin only), suggest_category.json (Kotlin only, D-049), match_card_purchase.json (Kotlin and the web only, D-170, §14.5.8). { "format": 1, "function": "compute_split", "cases": [ { "name": "50/50 odd amount, payer gets the extra öre", "input": { "amount_ore": 1001, "payer_user_id": "a", "user_ids": ["a", "b"], "spec": { "mode": "ratio", "bp": { "a": 5000, "b": 5000 } } }, "expected": { "ok": { "a": 501, "b": 500 } } }, { "name": "ratio does not sum to 10000", "input": { "amount_ore": 1000, "payer_user_id": "a", "user_ids": ["a", "b"], "spec": { "mode": "ratio", "bp": { "a": 5000, "b": 4000 } } }, "expected": { "error": "bp_sum_not_10000" } } ] } Input keys are the snake_case parameter names of the Rust signatures. For the Kotlin-only analytics functions they are the snake_case names of the Kotlin parameters and fields: spend_series takes expenses ([{"date", "account_id", "category_id", "amount_ore", "shares"}]), range ({"start", "end_inclusive"}), granularity, measure, group_by; resolve_range takes preset, today, earliest_expense, custom_start, custom_end; suggest_category takes description (string), history ([{"description", "category_id", "expense_date", "created_at"}]), keywords ([{"keyword", "match", "default_key"}] in table order, match one of token, prefix, phrase), active_categories ([{"id", "default_key"}], default_key null for a custom category) and fallback (category id or null), exactly as in contracts/test-vectors/suggest_category.json (aa765bb); the unicode parameter has no key (the test binds the platform implementation). spec is {"mode":"ratio","bp":{…}}, {"mode":"exact","ore":{…}} or {"mode":"full","bearer_user_id":"…"}. Outputs: compute_split {"ok": {user: öre}}; compute_balances {"ok": {"per_account": {...}, "global": {...}}}; propose_allocation {"ok": {"allocations": [{"account_id","amount_ore"}], "excess_ore": n, "over_settled_account_ids": [...]}}; validate_settlement {"ok": null}; over_settled_accounts {"ok": [ids]}; spend_series {"ok": {"buckets": [{"key","start","end_inclusive","totals","total"}], "group_totals": {...}, "grand_total": n}} with measure input "household" or {"share": "a"}, and dates as strings; resolve_range {"ok": {"start","end_inclusive"}}; suggest_category {"ok": "<category id>"} or {"ok": null} (it has no error case). Errors: {"error": "<token>"}. Minimum cases M1 must include (more are welcome): compute_split: every row of the §9.1 example table; full on payer; full on non-payer; exact valid; exact sum mismatch; exact negative; amount 0; amount 1 000 000 001; amount 1 000 000 000 with 3333 bp; bp 10001; three user ids; payer not in users; map keys not matching users; one error case per SplitError value. compute_balances: empty; one account with the two expenses (1001, payer a, 50/50) and (100, payer b, a 6000 bp) giving a +440, b −440, then adding settlement b → a 440 giving zeros; two accounts with opposite signs and a global sum; an account in account_ids with no rows (zeros). propose_allocation: payer owes in accounts X (created 2025-01-01T00:00:00.000Z, net −30000), Y (2025-02-01…, −20000) and is owed in Z (2024-12-01…, +10000): amount 40000 gives X 30000, Y 10000, excess 0; amount 60000 gives X 30000, Y 30000, excess 10000, over-settled [Y]; amount 5000 with only Z gives Z 5000 over-settled [Z]; all accounts archived and none owing gives the oldest; equal created_at ordered by id; no accounts gives no_accounts; amount 0 gives amount_out_of_range. validate_settlement: one case per SettlementError value plus a valid case with 3 allocations and one with 50. over_settled_accounts: none, one, an unknown account. spend_series: monthly and weekly over a range crossing a year boundary (ISO week 2026-W53 exists: 28 Dec 2026 to 3 Jan 2027), household and share measures, category and account grouping, empty buckets, edge-clipped buckets. resolve_range: every preset with today = 2026-10-17, ALL_TIME with and without an earliest expense, CUSTOM swapped. suggest_category (M12a): empty and punctuation-only descriptions (fallback); exact history match across case, ', ’, : and other punctuation ("Willy:s" and "WILLYS"); most often beats most recent; ties broken by expense_date, then created_at, then category id; first-token match when no exact match; exact match taking precedence over first token; an archived category in history skipped (the next category, then the next step); token, prefix and phrase keywords; longest keyword wins; equal length, earlier entry wins; a keyword whose category is archived falls through to the next matching entry; a renamed default category found by its key; diacritics kept (entre and entré distinct); & and digits kept (h&m, okq8); NFC applied to non-NFC input; surrogate pairs counted as one code point; no match gives fallback; fallback null gives null. M12a's file has 65 cases. 14.5.6 Category suggestion (Kotlin only) The rule is §9.11 (D-049). Types and functions in :domain, package se.hagstedt.kvitt.domain (landed with M12a, aa765bb). The records live in :domain, not in :core:model: the keyword table is data, not a UI contract, and default keys are open strings there. data class SuggestionHistoryEntry(val description: String, val categoryId: CategoryId, val expenseDate: LocalDate, val createdAt: String) enum class KeywordMatch { TOKEN, PREFIX, PHRASE } data class CategoryKeyword(val keyword: String, val match: KeywordMatch, val defaultKey: String) data class ActiveCategory(val id: CategoryId, val defaultKey: String?) interface UnicodeText { fun nfc(text: String): String fun isLetter(codePoint: Int): Boolean // general category Lu, Ll, Lt, Lm or Lo fun isDigit(codePoint: Int): Boolean // general category Nd } fun normalizeDescription(text: String, unicode: UnicodeText): String // CS-4 fun parseCategoryKeywords(csv: String): List<CategoryKeyword> // the §14.8 table; D-056 fun suggestCategory(description: String, history: List<SuggestionHistoryEntry>, keywords: List<CategoryKeyword>, activeCategories: List<ActiveCategory>, fallback: CategoryId?, unicode: UnicodeText): CategoryId? (CategoryId is se.hagstedt.kvitt.model.CategoryId; LocalDate is kotlinx.datetime.LocalDate.) UnicodeText exists because pure modules may not use java.* and kotlin.* has neither NFC nor general categories. :data binds it with java.text.Normalizer (NFC) and java.lang.Character (getType for L and Nd); the :domain tests bind the same. normalizeDescription applies nfc, then lowercase(), then walks the string by code points (a surrogate pair is one code point), deleting ', ’ and :, keeping &, letters and digits, and turning every other code point into a space; then it collapses spaces and trims. Inputs need not be NFC; the vectors include non-NFC strings. history holds non-deleted expenses only (the caller's job, as for every domain function). Expenses whose categoryId is not in activeCategories are ignored (CS-5). History ranking (CS-5 steps 1 and 2): the highest count wins; on equal count, the category whose latest matching expense is latest by (expenseDate, then createdAt); then the lower category id (string order). Keyword ranking (CS-6): among the matching entries, the longest keyword in code points wins, then the earlier entry in table order (keywords are passed in table order, §14.8). An entry resolves to the active category with that defaultKey; none means the next entry in that ranking is tried. parseCategoryKeywords (D-056) reads the text of contracts/category-keywords.csv: header keyword,match,default_key,source, entries in file order (table order), match mapped to KeywordMatch; a malformed table (wrong header, wrong column count, unknown match) throws IllegalArgumentException. Pure; shared by :data and :core:fakes, which read the bundled resource (§14.2.4, D-055). fallback is the step-4 category id (AC-8.6), computed by the caller; it is returned as given when no earlier step applies, also when the normalised description is empty. 14.5.7 Server analytics (Rust only, D-138) The rules of E-34 and E-35 (D-133). Pure functions in kvitt-domain (module analytics, no clock, no time zone): div_half_up, average, moving_average, percent_vs_average, occurs_in_period, and the constant MOVING_AVERAGE_WINDOW = 3 (D-128's window, shared with the phone's AnalyticsRules.MOVING_AVERAGE_WINDOW; a change changes both). kvitt-server (src/api/analytics.rs) picks the months and sums in SQL per group and month; no vector file covers these rules (unit and integration tests do). Months and today. A month is the calendar month of the stored expense_date (YYYY-MM-DD, no time zone). "Today" is the Europe/Stockholm date. The whole months are the N months before the current month (E-34: N = months; E-35's baseline: N = 3). "Current month so far" runs from the 1st of the current month through today; expenses dated after today never count. What counts. Non-deleted expenses only; settlements never (AC-14.6); expenses in archived accounts and in archived or deleted categories do (AC-14.9). household adds full amounts, my_share the requesting user's shares (AC-14.4). Averages. Total of the N whole months ÷ N, empty months counting as 0, rounded half away from zero to öre (div_half_up: 3/2 = 2, −3/2 = −2; 0 for N = 0). Percent. last_month_vs_average_pct compares the last whole month with the rounded average: (last − average) × 100 ÷ average in whole percent, half away from zero, negative below the average; null when the rounded average is 0. Moving average. Trailing over 3 months: each point with the two before it; the first points average what exists (1, then 2 points), half away from zero. Categories (E-34). A category is listed only when it has a non-zero amount in a whole month or in the current month; ordered by total_ore descending, then category id. household is the sum over all categories. Recurring (E-35). Per account and forecast month, recurring_ore is the sum over the account's non-paused, non-deleted templates that occur in that month, once per template and month (templates are monthly only, on day_of_month, §9.5): start_period ≤ month, month ≤ end_period when set, and month > last_generated_period when set (occurs_in_period). For my_share it is the share a generation would write today (mode default: the account's current default ratio). Baseline (E-35). The account's spend over the last 3 whole months, expenses generated from a template excluded, ÷ 3, half away from zero (D-133); months without spend count, so a new account reads low. current_month_ore is the current month so far, generated expenses included. 14.5.8 Card purchase matches (Kotlin and web only, D-170) The rule is §9.12 CP-10. :domain (package se.hagstedt.kvitt.domain) and web/src/lib/domain/; not in Rust (the server never suggests matches). Pure: dates are passed in, no clock. data class MatchablePurchase(val amountOre: Long?, val date: LocalDate, val direction: String) // direction "debit" or "credit" data class MatchableExpense(val id: String, val amountOre: Long, val date: LocalDate, val createdAt: String, val linkedByViewer: Boolean) fun matchCardPurchase(purchase: MatchablePurchase, expenses: List<MatchableExpense>, windowDays: Int, max: Int): List<String> Returns the ids of the expenses with the purchase's amountOre, |date − purchase.date| ≤ windowDays and linkedByViewer false, ordered by the absolute day difference, then createdAt descending, then id ascending, at most max; empty for a credit purchase or amountOre null. CP-10 calls it with windowDays 3 and max 3; "Välj en annan utgift" is a different list (any amount, 14 days, CP-10) and has no vector. Callers pass non-deleted expenses only. Vectors (match_card_purchase.json, K1 writes them with a Python reference in tools/contracts-check.py; format §14.5.5, input keys purchase {"amount_ore", "date", "direction"}, expenses [{"id", "amount_ore", "date", "created_at", "linked_by_viewer"}], window_days, max; output {"ok": [ids]}): no expenses; exact amount same day; ±3 days included, 4 days excluded; a different amount by 1 öre excluded; one linked by the viewer excluded; ordering by day difference, then created_at, then id; more than max candidates cut; a credit purchase; a null amount; a window across a month and a year boundary. 14.6 Push payload v1 FCM HTTP v1 message the server sends, one per target device (POST https://fcm.googleapis.com/v1/projects/kvitt-1337/messages:send): { "message": { "fid": "<device fcm_token>", "android": { "priority": "high", "ttl": "86400s" }, "data": { "v": "1", "type": "expense_created", "entity_type": "expense", "entity_id": "01929c5e-1111-7aaa-8bbb-000000000001", "actor_user_id": "0192…", "count": "1" } } } message.fid holds the device's fcm_token, which is the Firebase Installation ID the phone registered (D-083, D-096). FCM HTTP v1 deprecates message.token ("Use fid instead"); token, fid, topic and condition are mutually exclusive, and the server sets only fid. The database column and the E-17 field keep the name fcm_token. contracts/examples/push/*.json use fid. Data-only messages (no notification block), all values strings. Types (exhaustive): type entity_type entity_id actor_user_id count Sent to expense_created expense expense id creator 1 other user's devices expense_updated expense expense id editor 1 other user's devices expense_deleted expense expense id deleter 1 other user's devices settlement_created settlement settlement id creator 1 other user's devices settlement_updated settlement settlement id editor 1 other user's devices settlement_deleted settlement settlement id deleter 1 other user's devices recurring_expense_created expense expense id template creator 1 both users' devices sync_batch "" "" pusher number of notifiable changes, as a string other user's devices Server sending rules: Sending happens on one background task fed by a bounded queue (capacity 100; when full, the oldest message is dropped with a warning log). It never delays an HTTP response. Authentication: the sender signs an RS256 JWT with header kid = the service account's private_key_id, exchanges it for an access token and caches the token until 5 minutes before its expiry (§6.3). Retries (D-038): one send plus up to three retries after 1 s, 5 s and 25 s (at most four sends) on 429, 5xx and network errors. On 401 the cached access token is dropped and that message is not retried; other 4xx are not retried. Retries run inside the single sender task, so one failing device can hold the queue for up to 31 s; accepted for two users. FCM UNREGISTERED or HTTP 404 for a token clears that device's fcm_token, only if the stored token is still the one that was sent (a token the phone replaced meanwhile is kept). Push is disabled (NoopPushQueue, one start-up warning) when the credentials file is missing or unusable (treated alike). Phone handling (:adapter:fcm's PushMapping maps the message to PushEvent(type, entityType, entityId, actorUserId, count), a :core:model type in model/Push.kt since D-095; :app handles it in an expedited WorkManager job, D-085): Call syncForPush and wait for it up to 20 seconds. Build the notification text from Room per §13.3 copy (or the generic text if the sync failed or the entity or its actor is missing locally). Channel id activity, name "Activity" / "Aktivitet", importance default. Notification id = hash of entity_id (so an update replaces the create's notification); sync_batch uses id 1. Tap opens S-8 or S-10 for the entity; Home for deletions, sync_batch and the generic notification (D-085). Unknown type or v other than 1: sync only, no notification. Card purchases send no push (D-161, D-171): nothing about a card purchase or connection is put in an FCM message, and no type is added; the payload stays version 1. An expense created from a purchase sends expense_created like any other expense (AC-13.1). A notification for new card purchases is OQ-7. 14.7 Module layout and ownership map Repository layout (paths are binding): SPEC.md CLAUDE.md README-agents.md PLAN-*.md .gitea/workflows/ (Gitea Actions image build, M2c-pi) contracts/ openapi.yaml category-keywords.csv schema/server-v1.sql schema/migrations/{0002_categories_v2.sql, 0003_device_version_name.sql, 0004_card_purchases.sql} test-vectors/*.json examples/<E-id>-<name>/{request,response}.json, examples/errors/<code>.json, examples/sync/*.json, examples/push/*.json docs/ HANDOFF.md decisions.md ux/ spikes/ (spikes/k0/: K0's local test app, D-176) validation/ prompts/ tools/ gradle-serial.sh clean-builds.sh install-git-hooks.sh git-hooks/ dependency-report/ contracts-check.py server/ Cargo.toml (workspace) Cargo.lock Dockerfile rust-toolchain.toml crates/kvitt-domain/ src/{lib.rs, split.rs, balance.rs, allocation.rs, settlement.rs, recurring.rs} tests/vectors.rs crates/kvitt-server/ migrations/{0001_init.sql, 0002_categories_v2.sql, 0003_device_version_name.sql, 0004_card_purchases.sql} src/{main.rs, lib.rs, config.rs, error.rs, router.rs, openapi.rs, auth.rs, time.rs} src/db/{mod.rs, pool.rs, sequence.rs} src/wire/{mod.rs, user.rs, device.rs, invite.rs, account.rs, category.rs, expense.rs, settlement.rs, recurring.rs, audit.rs, sync.rs, analytics.rs, card.rs} src/api/{mod.rs, health.rs, setup.rs, invites.rs, landing.rs, me.rs, pictures.rs, devices.rs, accounts.rs, categories.rs, recurring.rs, proposal.rs, apk.rs, sync.rs, rate_limit.rs, rows.rs, validate.rs} src/tasks/ src/sync/ src/audit/ src/push/ src/cards/{mod.rs, providers.rs, api.rs, fetch.rs, poller.rs, callback.rs} src/cards/enable_banking/{mod.rs, mapping.rs} (K1, D-160; the card wire types in src/wire/card.rs, the row helpers in src/cards/mod.rs, D-188) src/cli/{mod.rs, bootstrap.rs, pair_device.rs, rotate_epoch.rs, healthcheck.rs, invite_partner.rs} tests/ tests/common/{mod.rs, sync_fixtures.rs} tests/cards_api/ (K1: against a local Enable Banking stub) (shared harness, included through #[path] by every test binary) crates/kvitt-import/ src/ data/splitwise_categories.csv tests/fixtures/ android/ settings.gradle.kts build.gradle.kts gradle.properties gradle/{libs.versions.toml, gradle-daemon-jvm.properties, wrapper/} build-logic/ (convention plugins, architecture check) core/model/ core/design/ core/fakes/ domain/ data/ adapter/fcm/ feature/{onboarding, home, account, expense, settle, analytics, settings, cards}/ app/ web/ (the web client, D-131, §15) package.json package-lock.json vite.config.ts tsconfig.json eslint.config.js index.html src/{app, api, i18n, design, components, lib}/ src/api/schema.d.ts (generated from contracts/openapi.yaml) src/features/{auth, home, accounts, expenses, search, export, settle, analytics, settings, cards}/ infra/ build-images.sh publish-apk.sh README.md RESTORE.md .shellcheckrc npm/kvitt.conf pi/{compose.yaml, .env.example, .gitignore} pi/.env, pi/secrets/, pi/out/ (git-ignored) (copied to /home/jacobhagstedt/kvitt on the Kvitt Pi, D-125) dev/{compose.yaml, .env.example, lib.sh, build.sh, up.sh, logs.sh, backup.sh, copy-google-services.sh} dev/data/, dev/backups/ (git-ignored) backup/{Dockerfile, backup.sh, healthcheck.sh} secrets/ (git-ignored) Ownership (an agent edits only paths its milestone owns; anything else needs the orchestrator): Paths Owner After the owner lands SPEC.md, CLAUDE.md, README-agents.md, docs/HANDOFF.md, docs/decisions.md, PLAN-*.md, prompts/, tools/ (except tools/contracts-check.py) docs agent briefed by the orchestrator same contracts/**, tools/contracts-check.py M1 contract-change plans only (§14.8) server/Cargo.toml, server/Cargo.lock, every crate's Cargo.toml, server/rust-toolchain.toml, server/Dockerfile, server/crates/kvitt-domain/** M2a contract-change plans only for kvitt-domain; M3, M4 and M9 may add dependency lines to a crate's Cargo.toml (second to land resolves Cargo.lock on rebase) kvitt-server: migrations/, src/{main,lib,config,error,router,openapi,auth,time}.rs (including the serve and migrate code), src/db/**, src/wire/**, src/api/{mod,health,setup}.rs, src/cli/{mod,healthcheck}.rs, M2a's own tests (any tests/*.rs without the prefixes core_, sync_, scheduler_, push_) M2a contract-change plans; M3/M4 may add one line per new module to mod.rs files they need; M3 edits the one marked rate-limit line in router.rs (D-015) kvitt-server: src/api/{invites,landing,me,pictures,devices,accounts,categories,recurring,proposal,apk,rate_limit}.rs, src/cli/{bootstrap,pair_device}.rs, tests/core_*.rs (M3's tests are one binary, tests/core_api/) M3 (M2a creates the shells, D-004) later server plans kvitt-server: src/api/sync.rs, src/tasks/**, src/sync/**, src/audit/**, src/push/**, src/scheduler/**, src/cli/rotate_epoch.rs, tests/sync_*.rs, tests/scheduler_*.rs, tests/push_*.rs (M4's tests are the binaries tests/sync_api/, tests/push_fcm/, tests/scheduler_daily/; its scheduler is src/tasks/scheduler.rs; there is no src/scheduler/; since the server overhaul (8cb42f8) every test binary includes the shared harness tests/common/mod.rs and tests/common/sync_fixtures.rs through #[path], replacing tests/core_api/common.rs and tests/sync_api/m4.rs) M4 (M2a creates the shells, the tasks::start stub and the AuditWriter/PushQueue traits with no-op implementations as described under "Server seams" in §6.3, D-004, D-015) later server plans; the trait signatures change only with M3, M4 and M9 agreeing through the orchestrator server/crates/kvitt-import/** M9 (M2a creates a crate that builds with a usage-only main.rs, D-004) same android/settings.gradle.kts, android/build.gradle.kts, android/gradle.properties, android/gradle/**, android/build-logic/**, the module shells (build file, manifest, one empty entry composable per feature) of :core:design, :data, :adapter:fcm and every :feature:* (D-004) M2b later plans may add catalog entries and module includes (rebase resolves) android/core/model/**, android/domain/** M2b contract-change plans only android/core/fakes/** M2b M7x add files only under fakes/<feature>/ android/core/design/** M6 (fix pass M6b, landed b24c8b5) M7x may not edit; requests go through the orchestrator; later design plans android/data/** M5 (M2b created the Room 3 entities, KvittDatabase v1 and the exported schema, D-012) later data plans; the exported schema is a contract file (§14.8) android/adapter/fcm/**, android/app/** (after the M2b shell) M8 later integration plans android/feature/onboarding/** M7a M7g (feature cleanups), later feature plans android/feature/home/**, android/feature/account/** M7b M7g (feature cleanups), later feature plans android/feature/expense/** M7c M7g (feature cleanups), later feature plans android/feature/settle/** M7d M7g (feature cleanups), later feature plans android/feature/analytics/** M7e M7g (feature cleanups), later feature plans android/feature/settings/** M7f M7g (feature cleanups), later feature plans infra/** M2c-dev, then M2c-pi (D-001) M10 updates runbooks .gitea/workflows/** M2c-pi (D-023) later infra plans git-ignored infra/secrets/** in the main checkout M2c-dev (D-022), then M2c-pi M8 copies google-services.json from it (§10.7) docs/ux/** U1, U2 M12 (D-054): contracts/category-keywords.csv, contracts/schema/migrations/**, contracts/test-vectors/suggest_category.json and the other contracts/** edits of §11.2 row M12a, tools/contracts-check.py, android/domain/** (suggestCategory, UnicodeText) M12a (contract-change plan, landed aa765bb) contract-change plans only M12 (D-054): contracts/openapi.yaml (DefaultCategoryKey) and the category examples M12a held back; kvitt-server migrations/0002_categories_v2.sql, src/db/mod.rs (SCHEMA_VERSION), src/api/validate.rs (token lists), src/wire/category.rs and src/wire/mod.rs (key enum), their tests; kvitt-import data/splitwise_categories.csv, src/categories.rs and its tests M12b (contract-change plan, landed 6eaccec) the usual owners M12 (D-054): android/core/model/** (enums, icons, ExpenseRepository), android/data/** (UnicodeText binding, suggestCategory, the build-time copy of the keyword table, D-055), android/core/fakes/** (defaults, fake suggestCategory) M12c (contract-change plan, landed b09f322) the usual owners D-059: android/core/model/** (ExpenseEditorOptions, CategoryRepository), android/data/** (frequentCategoryIds, deletable), android/core/fakes/** (both, outside the fakes/<feature>/ folders) M12d (contract-change plan, landed 557af7e) the usual owners; M7x keep their fakes/<feature>/ folders web/** except the feature folders below and web/src/api/schema.d.ts's regeneration (D-134) W0 later web plans; W1 to W5 may add dependency lines to web/package.json (second to land resolves web/package-lock.json with npm install on rebase) web/src/api/schema.d.ts (generated) W0 regenerated by whichever plan changes contracts/openapi.yaml, in the same landing (§15.3) web/src/features/home/**, web/src/features/accounts/** W1 (W0 creates the placeholder pages) later web plans web/src/features/expenses/**, web/src/features/search/**, web/src/features/export/** W2 (W0 creates the placeholder pages) later web plans web/src/features/settle/** W3 (W0 creates the placeholder page) later web plans web/src/features/analytics/** (W-9, W-10, W-11) W4 (W0 creates the placeholder pages) later web plans web/src/features/settings/** W5 (W0 creates the placeholder page) later web plans W7 (D-132, D-133): server/**, contracts/**, tools/contracts-check.py, .gitea/**, infra/build-images.sh, infra/dev/** W7 (contract-change plan for contracts/**) the usual owners W6 (D-133): android/feature/analytics/**, and for the Insights contract android/core/model/**, android/data/**, android/core/fakes/** W6 (contract-change plan, §14.8) the usual owners K0 (D-176): docs/spikes/k0/** (the test app of 2ce317f; its key, config and state in the git-ignored docs/spikes/k0/.local/, root .gitignore), docs/spikes/K0-enable-banking.md K0 docs agent (the report is a deliverable, kept) K1 (D-158 to D-175): server/**, contracts/**, tools/contracts-check.py, infra/pi/compose.yaml, infra/pi/.env.example, infra/dev/**, infra/npm/kvitt.conf, infra/README.md (step 4's block and the card runbook entry), and web/src/api/schema.d.ts for its regeneration only K1 (contract-change plan for contracts/**) the usual owners K2 (D-169, D-170, D-172, D-173): android/feature/cards/** (new module), and as a contract-change plan android/core/model/**, android/domain/** (matchCardPurchase), android/data/** (Room 2, exported 2.json), android/core/fakes/**; android/core/design/** (the fourth destination, nav_cards), android/feature/account/** (S-5's action), android/feature/expense/** (S-7's prefill, S-8's line), android/feature/settings/** (S-13's row), android/app/** (navigation, deep link, bindings), android/settings.gradle.kts and android/gradle/libs.versions.toml (the module and androidx.browser), docs/ux/strings.csv (the card keys of §13.3) K2 the usual owners K3 (D-174): web/src/features/cards/** (new), and in W0's shared code the route, the sidebar entry and web/src/lib/domain/ (matchCardPurchase); web/src/features/expenses/** (W-5's prefill, W-6's card line); web/src/features/accounts/** (W-3's "Från kortköp"); web/src/features/settings/** (W-13's row); the regenerated i18n dictionaries; as built also web/src/api/cards.ts and its test, web/src/test/cards.ts, web/vite.config.ts (/cards in the dev proxy), web/scripts/gen-icons.mjs and web/src/design/icons.generated.ts, web/src/app/Shell.test.tsx (ratified by the orchestrator at landing, faeb752) K3 later web plans docs/validation/<file> the milestone that names the file Module shells (D-004): a shell file or module created by M2a or M2b in a path owned by a later milestone holds only what makes the build and the 501 stubs work; the later milestone owns it from the moment the shell lands and writes the body. Strings: each feature module has its own src/main/res/values/strings.xml and values-sv/strings.xml with keys prefixed by the feature name; shared strings (the notification copy included) live in :core:design; :app holds only the app name; lint MissingTranslation is an error in every module (§6.2, D-017). Keys come from docs/ux/strings.csv (§13.4). 14.8 Contract files and the change rule Contract files (exhaustive): contracts/openapi.yaml, contracts/schema/server-v1.sql, the locked migration texts contracts/schema/migrations/*.sql (0002 since D-054, §14.1.1; 0003 since D-090, §14.1.2; 0004 since D-167, §14.1.3, committed by K1), contracts/category-keywords.csv, contracts/test-vectors/*.json, contracts/examples/**, the Room exported schema android/data/schemas/** (version 1 exists since M2b, D-012; version 2 by K2, D-173), android/core/model/** (the UI contract and domain types), the sync protocol (§14.4) and the push payload (§14.6). contracts/category-keywords.csv (D-049) is the keyword table of §9.11 CS-6: UTF-8 without BOM, \n line ends, header keyword,match,default_key,source, no quoting. keyword is non-empty and already normalised (CS-4 applied to it gives it back), unique in the file; match is token, prefix or phrase; a token or prefix keyword has no space and a phrase keyword has at least one; default_key is a key of AC-7.2 other than other; source is data (learned from the household's export) or curated, documentation only. Rows are sorted by default_key, then keyword, in code-point order. The phone bundles it through a build-time copy (D-055: :data:copyCategoryKeywords and :core:fakes:copyCategoryKeywords, no committed copy, a missing file fails the build, a :data test asserts byte identity and these rules, §14.2.4); M12a seeds the file from docs/ux/category-keywords.csv (148 entries). Changing an entry is a contract change like any other. Representational edits to contracts/openapi.yaml (key order, $ref naming, description wording) do not change meaning and need no spec bump or decision entry; they are listed in the report of the plan that made them (D-016). The OpenAPI equality test compares parsed values, not text. The equality test (server/crates/kvitt-server/tests/openapi_contract.rs, D-005) parses both documents and compares them after exactly these normalisations, every one representational; anything else that differs fails the test: Key order is ignored (objects compared as maps). Every local $ref is inlined, discriminator mapping values included, so component naming and placement do not matter. description and example/examples keywords are dropped (properties named description are kept; summary and operationId are compared). A nullable type array type: [T, "null"] equals oneOf with {type: "null"}; nested oneOfs are flattened and compared as sets. const: v equals a single-value enum: [v]; enum values and required lists are compared as sets. required: false and deprecated: false are dropped; a path parameter is always required. Parameters are keyed by (in, name). Each operation is compared on its effective security (its own security, else the document's). The document-wide rules of §14.3.1 and §14.3.2 live in one place on the generated side, the CommonRules modifier in server/crates/kvitt-server/src/openapi.rs, never in a handler annotation: the common request headers and the X-Kvitt-Server-Version response header on every operation, the always-possible error responses of §14.3.2 (authenticated and unauthenticated sets), the document-level device security, and response headers marked required. Rule: a change to any other contract file, or a semantic change to contracts/openapi.yaml or to §14 of this spec, requires, landed together by the orchestrator: a spec version bump (in the header and the change log), a docs/decisions.md entry, and the matching implementation changes on both sides, or a plan that schedules them. A schema change also bumps the schema version (meta.schema_version and a new migration on the server, whose locked text is the contract file contracts/schema/migrations/<NNNN>_<name>.sql, §14.1.1; there is no server-v2.sql, and server-v1.sql stays the text of 0001; a new Room version and migration on the phone). A sync protocol change bumps X-Kvitt-Protocol; a push payload change bumps v. Numbers come from the orchestrator's brief. Implementation agents never edit SPEC.md or docs/decisions.md: they put the proposed spec text and decision entry in their report, and the orchestrator has a docs agent record them (CLAUDE.md › Orchestration). Compatibility (v0.35, card purchases). The K1 server (schema 4) works with every older APK and web build: they never call /cards/*. A K2 APK against a server before schema 4 gets 404 not_found from E-40 and shows the Kortköp tab's empty state, and E-36 fails, so S-24 shows its error state; nothing else changes. K1 is therefore deployed before the K2 APK is published, as M12e's rule below asks. Compatibility (v0.13, M12e). The phone's DTOs give new wire fields no default, by design, so a phone running the M12e APK against a pre-M12e server (schema 2) cannot pair (E-3 lacks invite_kind) or list devices (Device lacks app_version_name). The server, the development stack included, is rebuilt and redeployed (migration 0003 runs at start) before the new APK is installed. Phones running an older APK work against the new server: they ignore the unknown fields and the server ignores a missing X-Kvitt-App-Version-Name. 15. Web client Owner interview 2026-10-21 (D-129 to D-134). Kvitt has a web client, built in web/ and served by kvitt-server under /app/. It is a second way into the same household: the same server, the same rules, the same data, read and written through the same API (§7, §14.3, §14.4). Nothing in the phone app changes because of it, except the Insights section of W6 (§15.8). This section is binding for the web plans W0 to W5 and for the web parts of W7; FR-21 holds the acceptance criteria. Status (2026-10-24, D-211). W0 to W7 and W0b are landed; the web client is live at https://kvitt.suorra.duckdns.org/app/ in image v1.0.3, paired from the owner's laptop browser and checked by the owner across its pages (§11.4). K3 (the card purchases of FR-22 on the web, W-21 to W-23) landed faeb752 (D-201 to D-207, v0.40) and ships in image v1.0.5; its owner steps (PLAN-K3 §8) follow that deploy. 15.1 Scope (D-129) Parity. Everything the Android app does, except what only makes sense on a phone: the phone pairing flow (S-1's server field, kvitt:// links, S-3 as a separate screen, S-18 as a separate screen), push notifications (FR-13), offline use and the sync screen (FR-15, S-16), the in-app update (FR-16, S-17). In: Home balances, account detail, account editor, expense add, edit and delete, expense detail with the audit timeline, settle up and settlement detail, analytics (S-11, S-12 with the D-128 line chart), categories, recurring templates, devices, profile, invite partner and pair a device (admin), about; and since v0.35 the card purchases of FR-22 (D-174, K3: W-21 to W-23), with BankID by QR in the desktop browser. Extras the app lacks (web only): free-text search across descriptions and notes with amount and date filters (W-12); CSV export of the filtered expense list (W-12); keyboard shortcuts N new expense, / search, Esc close, ? help (W-20); a language choice (W-13). Advanced analytics (D-133) come from the server and are shown on the web (W-11) and later in the app (W6). Form. Designed desktop first and usable on a phone: one column under 720 px wide, a sidebar from 720 px. Swedish and English, like the app (G-8). Light and dark by prefers-color-scheme. Not a progressive web app: no service worker, no web app manifest, no offline use, nothing cached for offline. Not in scope: a receipt picture (none exists in the app, §2); the S-1 confirm step of OQ-6; anything §2 still lists. 15.2 Access and login (D-130) Login. A browser logs in with an invite code exactly like a phone pairs: E-3 POST /invites/accept with a device invite (the usual case: the owner creates one on S-21 or W-18 for himself or the partner), or a partner or admin_setup invite. The device name is Web · <browser> (the browser's name from the user agent, Web alone when unknown). display_name is sent when the login page's name field is filled; it is needed only for partner and admin_setup codes (E-3), and an invalid_request for a missing name shows the field's error. A pasted invite link (https://<host>/i/<CODE>[?from=…]) fills the code (§8.3 normalisation, as S-1). After a partner accept the web opens the profile page once (the S-2 step, AC-2.10); every other accept opens Home. Token. The bearer token is kept in the browser's localStorage and sent as Authorization: Bearer <token> on every API call (§8.2). It is never put in a URL, never logged, never shown. The browser is a device like a phone: listed on Devices (AC-3.1) with its name, revocable from another device like any device (AC-3.2), and a revoked or unknown token gets 401 (AC-3.3), on which the web forgets the token and shows the login page with the S-18 message (device_revoked) or the plain login page (unauthorized). Log out (W-13) forgets the token in this browser. The device stays on the Devices list, still valid, until it is revoked from another device, because a device cannot revoke itself (cannot_revoke_current_device, AC-3.2); the page says so. A sign-out endpoint that revokes the current device would be a contract change (§14.8) and is not part of v0.28. First use (owner, 2026-10-24, D-156): the web client is first used from a browser on the owner's laptop; the phones keep the app. Headers (§14.3.1): X-Kvitt-Protocol: 1; X-Kvitt-App-Version with the web build's version code and X-Kvitt-App-Version-Name with its version name (both from the build, W0; the name is at most 32 characters, so it shows on S-20 like a phone's); Accept-Language is the browser's own. No X-Kvitt-App: a browser cannot carry the app key (§8.5). The NPM gate (§8.5, §10.5.2, extends D-126). From outside the home LAN a request passes when it carries X-Kvitt-App with the key, comes from the LAN, is Let's Encrypt's challenge path, or its path is /app or starts with /app/, or its path is /invites/accept, or it carries an Authorization: Bearer header and its path does not start with /health, /setup/, /i/ or /apk/. Everything else still gets 444. So the invite landing page (/i/), /health, /setup/status and the APK downloads stay LAN-or-key only, with or without a bearer header; the web client sends its bearer on API calls only. Consequence (accepted). The server's authenticated routes become reachable from the internet by anyone who sends some bearer token: a wrong token gets 401 unauthorized and counts against its address's unauthenticated limit of §8.6 (the H-1 fix, D-115, keeps junk tokens from ever counting as accepted), so the bound is 60 such requests per minute per address. POST /invites/accept is reachable from the internet and bounded by the 10-failures-per-hour lockout of AC-2.12 and the code's 60 bits (§8.3). The web client's static files are public (they hold no data and no secret). The security review's threat model (§8.1) assumed a reachable API before D-126; the gate stays a perimeter against scanners, and the device token stays the authentication. Browser hardening. The /app/ pages get a Content-Security-Policy that allows only the server's own origin for scripts, styles, images (plus blob: and data:), fonts and API calls, with frame-ancestors 'none' (§10.5.2; the server sends the same policy itself on every /app/ response, with X-Content-Type-Options: nosniff, X-Frame-Options: DENY and Referrer-Policy: no-referrer, D-135, so the development stack behaves as the Pi; behind NPM its $kvitt_csp header applies like the D-117 headers). No third-party script, font or CDN at run time: everything the page loads is in the image. localStorage is readable by any script on the origin, so the policy's script-src 'self' is what protects the token. 15.3 Stack and layout (D-131) web/ at the repository root: Vite, React 19, TypeScript in strict mode, React Router 7, TanStack Query 5, openapi-typescript (types generated from contracts/openapi.yaml into web/src/api/schema.d.ts, generated and committed) and openapi-fetch as the API client, Recharts for charts, Vitest with Testing Library for tests, ESLint and Prettier, plain CSS modules. npm with a committed package-lock.json; Node 25 on the Mac. Exact versions are W0's, each the latest stable at the time (recorded in its report). Design. Tokens from docs/ux/design-spec.md §2 as CSS custom properties: the same colour roles (light and dark), category colours (§9.7), type scale, spacing, the 4/2 corner-radius language of the charts (D-097), the same icons (Material Symbols, Apache-2.0, bundled as SVG, never from a CDN). The typeface is the platform's system font stack (D-020's "no bundled font"), amounts with tabular figures. Components follow the design spec's anatomy where one exists (ledger rows, balance header, category tile, avatar, segmented controls); desktop layouts are W0's and each plan's, within the tokens. Strings. A small JSON dictionary per language (sv.json, en.json). A string that exists in docs/ux/strings.csv uses its key and its text; web-only strings get keys prefixed web_ and are listed in the plan's report (they are not added to strings.csv, which is the app's). Placeholders are named ({name}), not Android format arguments. As built (W0, web/README.md "Strings"): web/src/i18n/{sv,en}.json are generated from docs/ux/strings.csv plus web/src/i18n/web-strings.csv (the shared web-only strings, W0's), with numbered placeholders {1}, {2} in place of %1$s; each feature keeps its own strings in web/src/features/<name>/i18n/{sv,en}.json (keys web_<name>_…), merged at build time; a string two features render moves to web-strings.csv (83f5293). Both languages always have every key; the gate checks it. Language. Swedish when the browser's preferred language is Swedish, English otherwise (G-8); W-13 offers a choice that overrides it in this browser (localStorage). Money and dates. Integer öre everywhere, formatting per §9.8 (the web formats with the same rules and the same outputs as the app for the same input). The money functions of §14.5.2 (computeSplit, computeBalances, proposeAllocation, validateSettlement, overSettledAccounts) exist in TypeScript and pass contracts/test-vectors/*.json for those functions in a Vitest test; resolveRange and spendSeries (§14.5.4) pass their vectors (W4), the category suggestion of §9.11 passes suggest_category.json (W2), matchCardPurchase (§14.5.8, web/src/lib/domain/) passes match_card_purchase.json (K3, listed as ported). The rules live in kvitt-domain, :domain and the web's ports of them; the vectors keep the three equal (G-1). Source layout (agreed for W0 to W5): web/src/app/ (entry, providers, router with every route, layout shell, keyboard shortcuts), web/src/api/ (generated schema, client, token store, household snapshot and writes, §15.5), web/src/i18n/, web/src/design/ (tokens, global styles), web/src/components/ (shared components), web/src/lib/ (formatting, the money functions under lib/domain/, utilities), web/src/features/<name>/ (one folder per feature plan, each with its own pages, components, tests and strings). Routes: /app/ Home, /app/login, /app/accounts/:id, /app/expenses/new, /app/expenses/:id, /app/settle, /app/settlements/:id, /app/analytics, /app/analytics/:groupKind/:groupId, /app/insights, /app/search, /app/cards (K3, D-174), /app/settings/* (/app/settings/cards and /app/settings/cards/:id K3's); sub-routes and query parameters are the owning plan's. As built (W0b, 5305f37). Shared web pieces live once in web/src/components (AccountTile, PageStates, Timeline, OverflowMenu, SwitchRow, editor/), lib (categories, timeline, accountColors), api (errors, invites) and app (useToday). A feature never imports another feature (catalog.test.ts also fails when a feature uses another feature's web_ key). Amount fields follow the page language: sv , or . decimal with space grouping, en . decimal with , grouping. Recharts is its own chunk loaded by the analytics pages only (vendor 516 → 132 kB). The Vitest cache is off. The web's version code is the git commit count at build time, else KVITT_VERSION_CODE, else 1. As built (K3, faeb752). Shared card pieces: web/src/api/cards.ts (the card snapshot of §15.5 and the E-44 write, with cards.test.ts; in api/ because W-21 to W-23, W-5, W-6, W-3 and W-13 read it), web/src/test/cards.ts (fixtures and the fake server's card endpoints), /cards in the dev proxy of web/vite.config.ts, the icons credit_card, link_off and visibility_off in web/scripts/gen-icons.mjs and the generated table, the query names cardPurchase, attempt and provider in routes.ts QUERY with the builders cardsPath, connectCardPath and expensesNewPath({ cardPurchase }) (D-202). Web-only strings web_cards_* (load and catalogue failures, the catalogue's loading line, "Filter", the never-fetched failure, expense_already_linked, card_bank_unavailable, the empty "Välj en annan utgift" list) and web_expenses_card_load_failed, web_expenses_card_missing_title, web_expenses_card_link_failed; the rest are the §13.3 keys. The web gate (the third gate, beside the Android and server gates): npm run check in web/, which runs tsc --noEmit, eslint ., vitest run, vite build and the generated-types freshness check (it fails when web/src/api/schema.d.ts differs from what openapi-typescript generates from contracts/openapi.yaml). A change to contracts/openapi.yaml regenerates web/src/api/schema.d.ts in the same landing, by the agent that changes the contract; it is the one file under web/ that a contract-change plan may write. 15.4 Build and serving (D-132) server/Dockerfile gets a Node stage that builds web/ (npm ci, vite build); the runtime image carries dist/ at /app. The build context becomes the repository root (docker build -f server/Dockerfile .), so the Gitea workflow, infra/build-images.sh and infra/dev/** change with it and the workflow's sparse checkout adds web (and contracts if the web build reads from it; W2's keyword table does, §15.7) (W7; as built §10.3, D-137). The web client is part of the server image and its version: there is no separate publish, no separate container and no change to infra/pi/compose.yaml; a deploy (§10.10) ships both. kvitt-server serves the files when the directory KVITT_WEB_DIR (default /app) exists: GET /app/<file> for files in it, GET /app/ and every other path under /app/ that is not a file get index.html (the client-side router handles the path), /app without the slash leads to /app/. Without the directory, /app/* is 404 not_found. As built (D-135, 50a0d67, src/api/web.rs, a small handler without tower-http): GET /app → 308 to /app/; /app/ and /app/index.html serve index.html; a safe path naming a file serves it; any other path falls back to index.html, except a missing file under assets/, which is 404 not_found (a vanished hashed asset must fail, not load HTML). Cache-Control: assets/* public, max-age=31536000, immutable, index.html no-store, other files no-cache. Every /app/ response carries the CSP of NPM's $kvitt_csp web policy (§10.5.2) plus X-Content-Type-Options: nosniff, X-Frame-Options: DENY, Referrer-Policy: no-referrer. Path safety: at most 512 bytes and 8 segments, each 1 to 255 characters of [A-Za-z0-9._-] not starting with .; an unsafe path is never joined to the directory and falls back like a missing one. The routes are not in contracts/openapi.yaml (static files, not API). Rate limit §8.6 (D-136); KVITT_WEB_DIR §10.4. The development stack (infra/dev) serves the web client the same way, from its image. For work on the web client, npm run dev in web/ runs Vite's dev server with /app/ as its base and forwards API paths to a Kvitt server (W0 documents the setting); agents use a throwaway server (cargo run -p kvitt-server -- serve with a temporary KVITT_DATA_DIR), never the owner's development or Pi data. 15.5 Data: reads, writes, freshness Reads. Accounts, categories, templates, expenses, settlements, users and audit entries are readable only through GET /sync (§7). The web keeps an in-memory household snapshot built from it: after login and on every page load it pulls from since=0 in pages until has_more is false and applies rows as §14.4.2 step 3 does (by server_version; the web has no pending rows); afterwards it pulls from its cursor on window focus and after every write. A different epoch or a 409 cursor_ahead drops the snapshot and pulls from 0. Nothing is persisted across a reload except the token, the language choice and per-viewer conveniences (a remembered filter); there is no IndexedDB copy. GET /me (E-7), GET /devices, GET /invites and the /analytics/* endpoints (D-133) are read directly. Card purchases (K3, D-201). The card snapshot (E-40) is held in memory beside the household snapshot, pulled from 0 on load, from its cursor on focus, every 60 s and after every card write; card writes are sent at once. A 409 cursor_ahead pulls it from 0; rows apply by card_version, tombstones included; only the viewer's own rows ever arrive (CP-11). W-21 re-reads it every 2 s while a connection is fetching or in its first fetch (CP-2's interval), otherwise at the shared 60 s (D-201). Refreshing it re-reads only the snapshot, not the catalogue (E-36) or an attempt (E-38) (web/src/api/cards.ts). Computed in the browser, as the phone does: balances (§9.3, computeBalances), effect lines (§9.2), the settle-up proposal (§9.4, proposeAllocation), the S-11 and S-12 analytics (§14.5.4) and the D-128 line chart. The advanced analytics of D-133 are not computed in the browser. Writes. Expenses and settlements are written with POST /sync, one mutation per user action (a new UUIDv7 id for a new row, a new mutation_id per attempt, the browser's clock for updated_at), and the result is applied to the snapshot at once: accepted updates the row; a rejection shows its §14.4.6 reason on the page and changes nothing. Everything else uses its REST endpoint (§7) and applies the returned row. The web never queues a write: a network error shows "Kunde inte nå servern" (common_could_not_reach_server) and the form keeps its values (§9.9's rule, for every write). Pictures (E-11) are fetched with the bearer header and shown from a blob: URL. 15.6 Screens The web's pages. "Mirrors" names the app screen whose content, rules and states the page follows (§13.3 and docs/ux/design-spec.md); the web adapts layout to the desktop, not content. States per page: loaded, empty, loading (the first snapshot pull), error (a failed request, with retry), long content; there is no offline state. Navigation (W0): a sidebar from 720 px wide and a bottom bar under it, with Home, Card purchases (Kortköp, after Home, D-172, D-174; added by K3, faeb752), Analytics, Insights, Search and Settings; New expense is a button in the sidebar and on Home and account detail (the app's FAB). Dialogs close with Esc. Destination changes are instant (D-108). 15.7 Search, export and shortcuts (D-129) Search (W-12) runs in the browser over the snapshot (§15.5): non-deleted expenses whose description or notes contain the query, ignoring case; filters combine with AND. Settlements are not searched. Results sort by date, newest first. The query and filters live in the URL query string (q, min and max in öre, from, to, account, category, payer), so a search can be bookmarked (D-147). CSV export (W-12) downloads the filtered list as a file, one row per expense: date, description, category, account, payer, amount, each user's share, notes, with a header row in the page's language. The file format (D-146, W2 a65ab71): UTF-8 with a byte-order mark, ; separator, CRLF, RFC 4180 quoting, amounts in kronor with a decimal comma and no grouping ("1234,50") in every page language, ISO dates, one share column per household user ("Andel "); a text cell starting with =, +, -, @, TAB or CR gets a leading '; file name kvitt-utgifter-<YYYY-MM-DD>.csv (Swedish) or kvitt-expenses-<YYYY-MM-DD>.csv (English). It opens correctly in Numbers and Excel with a Swedish locale. The export is built in the browser; the server has no export endpoint. Keyboard shortcuts (W0 binds them in the layout shell; the targets are the owning plans'): N opens W-5, / opens W-12 with the search field focused, Esc closes the open dialog or editor (with the discard rule of the mirrored screen), ? opens W-20. N, / and ? do nothing while focus is in a text field. Category suggestion (W-5, §9.11): the web ports the rule and passes suggest_category.json; the keyword table is read at build time from contracts/category-keywords.csv (the single source, never copied by hand), as the phone does (D-055); as built it is a raw import, allowed by server.fs.allow in web/vite.config.ts (D-148). 15.8 Advanced analytics on the server (D-133) Owner, 2026-10-21: "These calculations should be put in the backend because I will want to see this in the app as well." New read endpoints under /analytics/* (authenticated, any device), designed by W7: per-category averages and trends per month, overall and per category; and a forecast of the next 2 calendar months per account. As built (v0.29, D-138): E-34 GET /analytics/trends (averages and trends, household and per category; the two endpoints merged into one) and E-35 GET /analytics/forecast (§7, §14.3.4); averaging, rounding and month rules §14.5.7. Forecast rule (settled): for each account and each of the next two calendar months, forecast = the sum of the account's recurring templates due in that month (the known future expenses: active, not paused, inside their start and end periods, §9.5) + the average per month of the account's non-recurring spend (expenses not generated from a template) over the last 3 whole months. The 3-month window is the constant of D-128's trailing moving average (AnalyticsRules.MOVING_AVERAGE_WINDOW, 3, counted in buckets there and in whole months here), shared, not a second number; the server holds its own copy of the value and a change to it changes both. AC-14.1 is revised: the phone keeps computing S-11 and S-12 offline from Room; the advanced analytics come from the server, online only (§9.9), on the web (W-11) and in the app (W6, an "Insights" section on S-11; as built 1c9856b, D-141 to D-143, v0.31). 15.9 Plans and parallel work (D-134) Plans with disjoint paths (§14.7), one Opus agent each in its own worktree. W0 and W7 run first, in parallel; W1 to W5 run in parallel after W0 lands; W-11 (in W4) and W6 consume W7's endpoints once W7 has landed (W4 stubs W-11 until then). Web agents build with npm in their own worktree (npm ci in web/); Gradle and the phone are not involved, so W1 to W5 do not queue on tools/gradle-serial.sh; at most one cargo build per worktree (a throwaway server for a manual check). 16. Change log Id Page Route Mirrors Must show (beyond the mirrored screen) Actions Plan W-1 Login /app/login S-1 (code and name only), S-18's message App name and one-line purpose; invite code field (12 characters in groups of 4, §8.3); name field for a first login; where the code comes from (S-21 on the owner's phone); errors invite_invalid, rate_limited, network Log in W0 W-2 Home /app/ S-4; S-3 while there is no partner Balance header, Settle up, active accounts with balance and this month's count, collapsed archived section (its open state kept for the page session, D-145), empty state with the "Du och är med" card in place of the balance header (D-145); no sync pill, no update banner, no pull to refresh New expense (N), Settle up, open account, New account W1 (934eee7) W-3 Account detail /app/accounts/:id S-5 Month groups with month totals, expense and settlement rows, archived badge New expense (/app/expenses/new?account=<id>), Settle this account (/app/settle?account=<id>, D-144), Edit, Archive / Unarchive, Delete; "Från kortköp" (/app/cards?account=<id>, while the viewer has a card connection, K3, AC-22.9) W1 (934eee7) W-4 Account editor /app/accounts/new, /app/accounts/:id/edit S-6 Name, default split with the 100,00 kr preview Save, Cancel W1 (934eee7) W-5 Expense editor /app/expenses/new (?account=<id> presets the account, D-144), /app/expenses/:id/edit S-7 Amount, description, category grid with the §9.11 suggestion for a new expense, account, date, payer, split modes default, ratio, exact, full with live shares, notes; validation per §9.6 inline; a rejected or failed save in a banner with "Visa nuvarande version", the typed values kept; browser controls in place of S-7's keypad, slider and summary row (D-148) Save, Delete (edit), Cancel (Esc, with the discard dialog); from a card purchase ?cardPurchase=<id> (D-202) prefills per CP-9 and an accepted save links it with E-44: an unknown or deleted purchase shows "Kortköpet finns inte längre", a failed link keeps the expense and says "Utgiften sparades men kunde inte kopplas till kortköpet" (D-205; K3) W2 (a65ab71); K3 (faeb752) W-6 Expense detail /app/expenses/:id S-8 Every field, shares and mode, "Recurring: ", the audit timeline (AC-12.4, AC-12.5), deleted state; for the card holder the card line of AC-22.10 with the purchase date in the list form (D-206) Edit, Delete; Ta bort koppling (K3) W2 (a65ab71); K3 (faeb752) W-7 Settle up /app/settle (?account=<id> one account, ?settlement=<id> editing a payment, D-144) S-9 Direction with swap, amount, allocation rows with debts and over-settle warnings, allocation errors as you type (D-149), remaining indicator, add account, date, note, "Föreslå igen" Confirm, Cancel W3 (f9a9bfb) W-8 Settlement detail /app/settlements/:id S-10 Payer, recipient, amount, date, note, allocations, timeline Edit (/app/settle?settlement=<id>), Delete W3 (f9a9bfb) W-9 Analytics /app/analytics S-11 Range, granularity, measure, group-by; total; stacked bars with legend; category and account breakdowns; "Visa som tabell" under each chart, bar labels as keyboard stops (D-152) Open a drill-down: a bar opens /app/analytics/bucket/<key>, a breakdown row /app/analytics/:groupKind/:groupId, the filter in the query string (D-151) W4 (1aecf51) W-10 Drill-down /app/analytics/:groupKind/:groupId (groupKind category, account or bucket; query range, from, to, interval, measure, group, bucket, D-151) S-12 with D-128's line chart and average overlays Title naming the filter, total, line chart for a category or account over the range, expense rows; its own period changes replace the query string (D-151) Open expense W4 (1aecf51) W-11 Insights /app/insights none (D-133) Per-category averages and trends per month (overall and per category) over 3, 6 or 12 whole months (default 6, D-152), the 2-month forecast per account with its parts (recurring, average) Choose category or account; choose months W4 (1aecf51) W-12 Search /app/search none (D-129) Free-text search in descriptions and notes (case-insensitive), filters for amount range, date range, account, category, payer, kept in the URL query string (D-147); result count and sum; expense rows Open expense; Export CSV of the filtered list (format D-146) W2 (a65ab71) W-13 Settings /app/settings S-13 Own and partner's avatar and name; rows Profile, Categories, Recurring expenses, Devices, Invites (admin), About, Language; "Anslut kort" (S-13's row: none, connected with valid_until in the detail form (D-206), or settings_cards_expired; K3); Log out Navigate; Log out W5 (3ebe57d); K3 (faeb752) W-14 Profile /app/settings/profile S-14 (and S-2 once after a partner login, as an intro remembered per browser device in kvitt.profileStepDone, D-154) Avatar with change and remove (file picker), display name Save W5 (3ebe57d) W-15 Categories /app/settings/categories, editor /app/settings/categories/new and /app/settings/categories/:id (D-153) S-15 List with archived section; editor with name, reset name, 33 icons, 14 colours, delete or archive with the reason Add, Edit, Reorder (drag, and by keyboard), Archive, Delete W5 (3ebe57d) W-16 Recurring expenses /app/settings/recurring, editor /app/settings/recurring/new and /app/settings/recurring/:id (D-153) S-19 List and editor as S-19 Add, Edit, Pause / Resume, Delete W5 (3ebe57d) W-17 Devices /app/settings/devices S-20 Rows per AC-3.1; this browser marked as "This device" Revoke (with confirmation; not this browser) W5 (3ebe57d) W-18 Invites /app/settings/invite (D-153; /app/settings/invites opens it too) S-21 Invite partner (before the partner joins) and pair a device; a created invite's code in groups of 4, link and expiry; pending invites Create, Copy (code and link, to the clipboard), Cancel W5 (3ebe57d) W-19 About /app/settings/about S-22 The web build's version name and code; the server's version and schema from E-1 /health when it answers (on the LAN), otherwise the X-Kvitt-Server-Version header of a fresh GET /me without the schema (the S-22 fallback, D-110, D-154; /health is closed from outside, §15.2) none W5 (3ebe57d) W-20 Keyboard help dialog on ? none (D-129) The shortcuts and what they do Close (Esc) W0 W-21 Card purchases /app/cards (?attempt=<id> after the bank's return, CP-2; ?account=<id> from W-3's "Från kortköp", which shows the purchases to handle and presets that account for "Skapa utgift", as S-27) S-23, S-27 (D-174) The header card with artwork, "Uppdaterad", "Uppdatera"; filters; day groups; rows with the match chip; the purchase as a side panel from 720 px (a dialog below) with the S-23 sheet's actions; "Skapa utgift" opens W-5 at /app/expenses/new?cardPurchase=<id> (plus &account=<id> when W-21 was opened from an account; D-144's parameter style), prefilled per CP-9, and saving links the purchase; W-6 shows the card holder the line of AC-22.10; with ?attempt= it polls E-38 until the attempt ends, then drops the parameter; states as S-23 without the offline one. As built: polling E-38 every 2 s; once ?attempt= is dropped, a connected attempt shows the snackbar "Kortet är anslutet", a failed one a banner "Det gick inte att ansluta kortet" and an expired one "Anslutningsförsöket tog för lång tid", each with "Försök igen" to W-22 ?provider= (D-204); E-40 re-read every 2 s while fetching (D-201); the expiring banner shows valid_until in the detail form (D-206); with ?account= it is S-27: title "Från kortköp", rows open W-5 directly, no filter chips, no panel (D-207) Uppdatera; filter; Skapa utgift; link; Välj en annan utgift; Ignorera; Ta bort koppling; Förnya med BankID K3 (faeb752) W-22 Connect card /app/settings/cards S-24, S-25 (D-174) The catalogue with artwork; for a card not connected, the history choice and "Anslut med BankID", which opens the bank's page in the same tab (BankID by QR on the computer); returning through the callback page's link lands on W-21. As built: ?provider=<id> opens the connect step (S-25) for that card, also from "Förnya med BankID" (D-202); history 7, 30, 90 or 180 days; E-37 with client web; only an https: auth_url is followed, anything else shows "Det gick inte att ansluta kortet" (D-203); a connected card's tile shows valid_until in the detail form (D-206) Anslut med BankID; open a connected card (W-23) K3 (faeb752) W-23 Card connection /app/settings/cards/:id S-26 (D-174) As S-26: status, valid_until, last fetch, history (a shorter one through E-41), the disconnect dialog with "erase handled purchases" (E-43 erase_handled) Change history; Förnya med BankID (W-22 ?provider=); Koppla från K3 (faeb752) Plan Paths Content W0 Web foundation web/** except the feature folders of W1 to W5 Scaffold, tokens, layout shell, router, login and token store, API client and household snapshot, i18n, formatting, shared components, money functions, test setup, the web gate; W-1, W-20 W1 Home and accounts web/src/features/home/**, web/src/features/accounts/** W-2, W-3, W-4 W2 Expenses and search web/src/features/expenses/**, web/src/features/search/**, web/src/features/export/** W-5, W-6, W-12, CSV export, the §9.11 port W3 Settle up web/src/features/settle/** W-7, W-8 W4 Analytics web/src/features/analytics/** W-9, W-10, W-11, the §14.5.4 port W5 Settings web/src/features/settings/** W-13 to W-19 W6 Android Insights android/feature/analytics/**, and as a UI-contract change (§14.8) android/core/model/**, android/data/**, android/core/fakes/** The D-133 endpoints on S-11 W7 Server web serving and analytics server/**, contracts/**, tools/contracts-check.py, .gitea/**, infra/build-images.sh, infra/dev/**, and web/src/api/schema.d.ts when it changes contracts/openapi.yaml §15.4, §15.8 K3 Web card purchases (D-174) web/src/features/cards/**; in shared code the route, the sidebar entry and web/src/lib/domain/ (matchCardPurchase); web/src/features/expenses/**, web/src/features/accounts/** and web/src/features/settings/** for W-5's prefill, W-6's card line, W-3's "Från kortköp" and W-13's row (§14.7) W-21 to W-23; landed faeb752 after K1 and K2 Version Date Change 0.1 2026-10-17 First version, written from the owner interview: scope, requirements, data model, stack, API outline, security, business rules, deployment, milestones, UX sprint brief, contracts (schema v1, Room v1, OpenAPI outline, sync protocol v1, domain functions and vectors, push payload v1, ownership map). 0.2 2026-10-17 Owner answers. D-001: development-first deployment on the Mac; M2c split into M2c-dev (now) and M2c-pi (after M8, before M10); registry is Gitea at http://gitea.lan (OQ-1 answered). D-002: local backup files deleted as soon as confirmed on Drive. D-003: Splitwise CSV format confirmed for English and Swedish exports, Swedish category names mapped, accounts "Hemma" and "Vardag" (OQ-2 answered). OQ-4 answered (Drive folder id). §10, §11, §12, §14.7 updated. Clarifications from M1 (no new decisions): non-deleted rows only into domain functions, analytics vector keys, sync push result key sets, E-1 503 body, optional/nullable request fields of E-3, E-12, E-17, E-33, since required on E-31, proposal amount range, bp above 10000, resolveRange edge cases, §9.6 limits not in JSON Schema, example directory names, not_implemented on no operation (§14.3, §14.4.3, §14.5). 0.3 2026-10-17 Orchestrator resolutions of the plans' open points. D-004: M2a and M2b create shell files and modules in later milestones' paths, ownership of Cargo.lock and every Cargo.toml (§11.2, §11.3, §14.7). D-015: server seams: middleware in router.rs, rate limit in src/api/rate_limit.rs on one marked line, src/tasks/ for M4, AuditWriter/PushQueue traits with no-op implementations, next_occurrence_date and day clamping in kvitt-domain (Rust only), M3 writes the recurring generation function, M4 lands after M3 (§6.3, §9.5, §11, §14.5.2, §14.7). D-016: the OpenAPI equality test compares parsed values; representational edits need no spec bump (§11.3, §14.8). D-017: feature convention, analytics types in se.hagstedt.kvitt.model.analytics, string placement and key prefixes, MissingTranslation in every module (§6.2, §13.4, §14.5.4, §14.7). D-018: empty fake scenario; resolveRange throws a typed IllegalArgumentException subclass for an incomplete CUSTOM range (§6.2, §14.5.4). D-019: ledger rows and expense editor fields in :core:design (§6.2, §11.2). D-020: no bundled font, Material 3 default typeface (§6.2, §13.4). D-021: sync_mutations pruning daily at 04:00 (§14.1, §14.4.9). D-022: development infrastructure as M2c-dev built it (c885aba): Firebase through the REST API with a gcloud token, no Firebase CLI, secrets and google-services.json in infra/secrets/ copied by infra/dev/copy-google-services.sh, Firebase resources and the kvitt-fcm service account (roles/firebasecloudmessaging.admin) exist; dev stack without Caddy or TLS, bind-mounted data, infra/secrets/ mounted at /secrets, env file infra/dev/.env.example, healthcheck used by compose; the server starts when KVITT_TRUSTED_PROXY does not resolve; new M2c-dev gate (§10 intro, §10.4, §10.7, §11.2, §14.7). D-023: M2c-pi allowances, HUMAN steps, .gitea/workflows/, secret modes for uid 1000 (§10.2, §10.3, §11.2, §14.7). D-024: release keystore command, kept outside the repository (§10.6). D-025: production import procedure and the /opt/kvitt/import bind mount (§10.2, §10.8). Without a decision id: exact Rust version pin shared by rust-toolchain.toml and the Dockerfile (§10.3); the §9.7 colour change lands before M6 (§11.1); per-screen states are U2's list (§13.3); landing page copy (§13.3, AC-2.5); M8 owns network security config, hardening, signing and version properties (§11.2); U1's gate names the six phase-1 screens (§11.2); category table path (§10.8); implementation agents never edit the spec or the decisions log (§14.8). 0.4 2026-10-17 Decisions from the M2a (06f48ef) and M2b (c277ee3) implementation reports. D-005: the eight normalisations of the OpenAPI equality test and the CommonRules modifier in openapi.rs (§11.3, §14.8). D-006: the wrong-bp-sum token is bp_sum_not_10000 with an explicit serde rename in Rust; Kotlin emits the same token (§14.5.1, §14.5.3). D-007: the no-unwrap rule enforced per crate with #![cfg_attr(not(test), deny(clippy::unwrap_used, clippy::expect_used))] (CLAUDE.md). D-010: screenshot tests with Roborazzi 1.76.0 on Robolectric 4.17, @Config(sdk = [36]), roborazzi.test.verify=true, re-record with recordRoborazziDebug (§6.2, §11.2). D-011: IncompleteCustomRangeException for an incomplete CUSTOM range; ALL_TIME with the earliest expense after today gives today..today (§14.5.4). D-012: Room 3 (androidx.room3 3.0.3, KSP only, SQLiteDriver with sqlite-bundled, migrations on an SQLiteConnection); M2b created the entities and KvittDatabase v1, whose exported schema 1.json is a contract file; M5 builds on them (§6.2, §11.2, §11.3, §14.2, §14.2.3, §14.7, §14.8). D-013: JDK 25 --add-exports/--add-opens for Robolectric in build-logic (§6.2). D-014: failOnNoDiscoveredTests off only for modules without src/test (§6.2). D-008 and D-009 unused. Clarifications without a decision id: exact Rust pin (1.99.1) shared by rust-toolchain.toml and the Dockerfile, TARGETARCH arm64 (shipped) and amd64, distroless pinned by digest (§6.3, §10.3); chrono stands (§6.3); kvitt-domain depends only on serde (§6.3, CLAUDE.md); AuditWriter and PushQueue as built (§6.3, §14.7); protocol check before token check (§6.3, §14.3.1); 405 with an empty body and the version header (§14.3.1); body limits as router layers (§8.6); app_version_code updated only from a present, parseable X-Kvitt-App-Version (§8.2); E-1 schema_version from a code constant; E-2 initialized means an admin user exists (§14.3.4); healthcheck uses the port of KVITT_BIND; cargo run -p kvitt-server -- <command> from the workspace root (§10.4); minSdk 36, compileSdk and targetSdk 37, Material 3 1.4.0 pinned beside the Compose BOM, AGP 9 check runs only the debug unit-test variant, version code and name from kvitt.versionCode/kvitt.versionName defaulting to 1/dev, feature convention documented in android/README.md (§6.2); FieldError.error may be validation_failed for §9.6 rules without a domain token (§9.6, §14.2.4); AnalyticsState has no error field and a missing custom date resolves as today (§14.2.4, §14.5.4); DrillDownState.title stays a String of unlocalised parts and S-12 formats its own title (§14.2.4); a settlement row in an account's list shows that account's allocation (AC-11.7, §14.2.4); the AnalyticsMeasure.Share / model.Share name collision is accepted (§14.2.4, §14.5.4). 0.5 2026-10-17 Decisions from the M3 (7869ec4) and M5 (8f0e156) implementation reports. M3: D-030 picture version after a removal, -removed marker, next version = highest on disk + 1, first upload 1 (AC-4.4, §10.4, E-10); D-031 failed accept = any 4xx but 429, refused until 60 minutes after the first failure, fixed windows (AC-2.12); D-032 rate-limit keying by token hash, 401 counts against the IP, never-accepted tokens refused when the IP is over, KVITT_TRUSTED_PROXY re-resolved every 60 s, last X-Forwarded-For entry, into_make_service_with_connect_info added by M4 (§8.6, §10.4, §11.3); D-033 resume moves last_generated_period only to a period at or after start_period (§9.5); D-034 strings stored trimmed, transparency flattened onto white, fcm_token non-empty or null, revoke clears fcm_token, idempotent archive keeps server_version, new category sort_order over non-deleted (§8.6, §9.6, AC-3.5, AC-4.4, AC-7.3, E-17, E-20, E-21, E-25, E-26). M5 (renumbered: its D-030 to D-033 are D-040 to D-043): D-026 cursor_ahead is epoch recovery (§14.4.2); D-027 clock_skew gives a new pending_mutation_id, and the phone re-stamps updated_at on the next attempt (orchestrator decision, follow-up open) (§14.4.5); D-028 periodic work kvitt-sync-periodic (§14.4.1); D-029 OnlineResult.Failed("network", null) (§14.2.4); D-040 whole-request push refusals count as no progress, 429 retries, 426 stops (§14.4.5); D-041 DataBindingsModule (§6.2); D-042 Room tests on Robolectric, migrations from the exported JSON (§6.2); D-043 pairing status and 426 version code in DataStore (§8.2, §14.2.2). D-035 to D-039 reserved for M4. Clarifications without a decision id: control characters restricted only in notes, newlines accepted in names and descriptions (§8.6); landing page without download button while no APK is published, 404 page, Referrer-Policy and Cache-Control headers (AC-2.5, §13.3); generation sets the template's updated_at (§9.5); E-28 accepts archived accounts and categories (AC-6.4); E-14 on an accepted invite is 204 with no change; /health from the healthcheck counts against loopback (§8.6); M3's tests in one binary tests/core_api/ (§14.7); sync triggers, batch and page sizes (AC-15.3, §14.4.1); 426 stops syncing until the installed version changes and HomeState has no update-required field (§14.2.4, §14.3.1); pictures always fetched at 512; NeedsInstallPermission once (AC-16.3); Rejection.summary, FieldChange display and RecurringTemplate.draft.date as documented in :data (§14.2.4); M8 contract requests (§11.3). 0.6 2026-10-18 Decisions from the M4 (15056dc) implementation report. D-035: a mutation whose mutation_id, entity_type or entity.id is unusable fails the whole request with 400 invalid_request; every other shape error is a per-mutation validation_failed (§14.4.4 step 3). D-036: POST /sync with 0 mutations is 422 batch_too_large, the code now reads "outside 1 to 100" (§9.6, §14.3.2, §14.4.4). D-037: a delete of a never-synced row runs the full step-8 validation; every rejection carries the stored row or null as current, also at steps 3 and 4; step 11 keeps the stored created_at; pushed ids must be canonical lowercase hyphenated UUIDs (§14.4.3, §14.4.4). D-038: FCM retries are one send plus up to three retries at 1 s, 5 s, 25 s; 401 drops the cached access token and is not retried, other 4xx are not retried; retries block the single sender task up to 31 s per device (§14.6). D-039: pruning deletes received_at strictly older than 90 days; seam change to D-015: tasks::start returns the AppState with the real push queue and serve builds the router from it, AppState::new defaults to SqlAuditWriter, NoopAuditWriter removed, NoopPushQueue kept for push disabled (§6.3, §14.1, §14.4.9; PLAN-M4). Clarifications without a decision id: §14.4.4 step 8 order is field rules, domain rules, references; a negative since is invalid_request and a pull reads one page in a single read transaction (§9.6, §14.3.4, §14.4.2); push runs in one BEGIN IMMEDIATE with a savepoint per mutation; the push queue is bounded at 100 and drops the oldest with a warning; the FCM JWT is RS256 with kid = private_key_id, the access token cached until 5 minutes before expiry, messages data-only with string values; UNREGISTERED or 404 clears the device token only if unchanged; an unusable credentials file disables push like a missing one (§6.3, §14.6); the scheduler reads the injected clock at least every 30 s, runs a missed job once after a forward jump and re-plans after a backward jump of more than a day (§9.5); rotate-epoch prints the new epoch, exit 0 or 1 on a database error (§10.4); serve uses into_make_service_with_connect_info (D-032 fulfilled, §8.6, §11.3); GET /i/ with an empty code is the HTML 404 (E-4); reqwest (rustls, aws-lc-rs, platform verifier) and jsonwebtoken added, so the arm64 image needs a C toolchain stage and the distroless image CA roots, to be confirmed by M2c-pi or M10; the dev image was rebuilt with them on the Mac on 2026-10-18 (§6.3, §10.3); M4's test binaries and scheduler path (§11.3, §14.7). 0.7 2026-10-18 Decisions from the M9 (50339ae) implementation report and the importer rehearsal on the real exports. D-044: nine Swedish Splitwise category names added to the §10.8 table and to splitwise_categories.csv with the key of their English equivalent (Städning and Verktyg - Övrigt utilities, Tjänster home, Cykel transport, Flyg travel, Spel entertainment, Kläder shopping, Livet - Övrigt and Utbildning other). D-045: reconciliation: the run commits only if each user's balance of the whole account equals the sum of the file's totals rows (one per currency, converted with --fx); a mismatch or a missing totals row rolls back and exits 4, a dry run reports the same, an account already holding other rows rolls back, a mismatch after any --fx conversion is reported but accepted (§10.8, AC-17.5). D-046: CLI semantics: --user takes a user id or an exact unique display name; no database is created or migrated, meta.schema_version must be 1; a dry run runs the full transaction and rolls back; exit codes 0 ok, 1 database or file error, 2 usage, 3 cannot import, 4 reconciliation mismatch; the import key uses an existing account's stored name; an empty description or one over 1000 code points makes the row invalid; descriptions over 100 code points are cut with the full text in notes; settlement notes cut to 200; both nets zero is mode full on the owner; idempotency through the existing import_key columns (§10.8, AC-17.5). M9 marked landed, M11 rehearsal recorded (§11.2, §11.3). 0.8 2026-10-18 Decisions from the owner's UX session (docs/ux/proposed-decisions.md UX-1 to UX-8 on branch UX-sprint). D-047: direction 3 "Kalas" with the muted palette, typeface per D-020 (§9.7, §13.4). D-048: navigation stays at three destinations, an "Aktivitet" tab not taken for v1; §13.2 binding. D-049: category suggestion from the description, new §9.11 (CS-1 to CS-7: new expenses only, manual choice wins, history most often then first token, keyword table, AC-8.6 default, no marker), AC-8.6, ExpenseRepository.suggestCategory (§14.2.4), Kotlin-only suggestCategory in :domain with the UnicodeText interface bound by :data and suggest_category.json as landed by M12a (aa765bb) (§14.5.5, §14.5.6), contract file contracts/category-keywords.csv (§14.8). D-050: S-1 display-name field on a first pairing (AC-2.4, §13.3). D-051: §9.7 hex values become the muted Kalas values from U2, token names fixed, slate and amber TODO(U2). D-052: "Utgiften sparades" without undo (S-7), archived account hides the FAB (S-5), per-account settle-up keeps the swap and an editable amount (S-9), avatar tokens avatar-1 and avatar-2 (AC-4.5), Swedish effect copy (AC-8.10). D-053: finer Splitwise mapping (§10.8). D-054: fourteen default categories (housing, insurance, children, fees added; AC-7.2), icons key, shield, account_balance (33), colours slate, amber (14), server schema 2 through migration 0002 rebuilding categories (§14.1.1, locked as contracts/schema/migrations/0002_categories_v2.sql, copied from M12a's file; no server-v2.sql, §14.8), importer schema check 2 (§10.8), enums in §14.2.4 and §14.3.3, E-1 schema_version 2; Room schema unchanged. New milestone group M12 "Category contract v2" (M12a contracts, then M12b server and M12c Android in parallel; M6 and M7c wait for M12c) (§11). 0.9 2026-10-18 Outcomes of M12b (6eaccec) and M12c (b09f322), U2 (landed 6da6b1b) and UX-9. D-055: the keyword table is copied from contracts/category-keywords.csv at build time by :data:copyCategoryKeywords and :core:fakes:copyCategoryKeywords (AGP generated resource directory), a missing file fails the build, packaged as se/hagstedt/kvitt/data/category-keywords.csv (and the fakes path in debug), no committed copy, a :data test asserts byte identity and the §14.8 rules; supersedes the android/data/src/main/resources copy (§11.2 M12c, §14.2.4, §14.7, §14.8). D-056: pure parseCategoryKeywords(csv) in :domain, shared by :data and :core:fakes (§14.5.6). D-057: DefaultCategoryKey declared in AC-7.2 order; the Rust wire enum, the OpenAPI enum and the 0002 CHECK list the ten v1 keys then the four new ones; wire values unaffected (§14.2.4). D-058: test harnesses seed users after the fourteen category seeds (server_version 15 and 16); E-7-me/response.json shows 15 and 16 and its test compares them again (§14.3.5). D-051 fulfilled: §9.7 hex values from docs/ux/design-spec.md §2.3; design-spec.md is the binding design document and strings.csv (558 rows, D-017 prefixes, plurals as key:one/key:other) the source of string resources (§13.4). D-059: UX-9 accepted as a contract change: ExpenseEditorOptions.frequentCategoryIds and CategoryRepository.deletable(id) with their readings and fallbacks (§14.2.4), new milestone M12d (§11, §14.7); M7a to M7f depend on M6 and M12d. Clarifications without a decision id: suggestCategory history is every non-deleted expense (pending included, all accounts, both users), active categories neither archived nor deleted, fallback last-used in the account if active else other, null account gives other; when other is archived and no active last-used exists the result is null and the editor shows no category until the user picks one (AC-8.6, §9.11 CS-5, §14.2.4); stored expense_date values are valid ISO dates (§9.6), so parsing cannot fail. §11.2: M12a, M12b, M12c, U1, U2 landed, M6 started 2026-10-18; dry run of 2026-10-18 (Vardag 1746 rows, 0 unmapped; Hemma 37 rows, 0 unmapped; both reconciled) (§11.2, §11.3). §10: development stack migrated to schema 2 on 2026-10-18 after a backup. PLAN-M12b: bundled SQLite is 3.51.x (3.51.3), not 3.50. 0.10 2026-10-18 Outcomes of M12d (557af7e) and M6 (7730a31) and two owner-approved string decisions. D-060: frequentCategoryIds holds only categories used in the account (possibly fewer than five or empty); filling to five and placing the selected category fifth stays in the editor; not a contract change (§14.2.4). D-061: a key for every active account (empty list when unused), none for archived accounts; ties by count, sort_order, then category id (§14.2.4). D-062: deletable is false for an unknown or deleted id; archived categories follow AC-7.6; fake delete and deletable share one rule (§14.2.4). D-063: charts on Compose Canvas in :core:design, not Vico (3.3.1 cannot meet design-spec §3.10); Vico stays in the catalog unused, removable later (§6.2). D-064: Material 3 Expressive against material3 1.4.0: ShortNavigationBar used; MaterialShapes, ButtonGroup, LoadingIndicator, LinearWavyProgressIndicator, medium extended FAB, button sizes, segmented list items, expressive slider, MotionScheme.expressive() and the increased shapes take fallbacks; fulfils design-spec §6 open point 5 (§6.2). D-065: sv and en month and weekday tables in DateFormatter; chart labels without dots; file sizes in SI megabytes with one decimal (§9.8). D-066: golden layout per component sheet × light/dark × sv/en, plus 200 % for long states, switched through a configuration context; M7a to M7f follow it (§6.2). D-067: English default name of restaurants is "Dining" (AC-7.2, strings.csv, :core:design). D-068: shared ledger_settlement_label ("Payment" / "Betalning") for the settlement row's type label; settlement row titles may wrap to 2 lines (3 at 200 %); an empty chart range shows only the 0 baseline (§13.3, §13.4). Without a decision id: :core:design described as built (§6.2); SyncStatusPill takes a failed flag until SyncSummary gets a "last attempt failed" field (§13.3, M8 request); M6's M8 contract requests LocalAvatarPictures/AvatarPictures (authenticated E-11 request from user id and pictureVersion), ProvideHousehold(me, partner), LocalKvittClock; design-spec §2.7 One UI font check at the M8 install (§11.3). §11.2: M12d and M6 landed, M7a to M7f started 2026-10-18. 0.11 2026-10-18 Outcomes of the M7 wave (M7a 1ea752c, M7e ea7d494, M7d 7380e50, M7b 0e1d99d, M7c 0b140aa, M7f c4ab35f) and the design-system fix pass M6b (b24c8b5); owner approved in advance. D-069: S-11 total caption " · Hushållet" / " · N veckor", label "Totalt · Min del" for my share, whole-month ranges for month presets and days otherwise, legend and stacking by sortOrder and AccountRepository.all() order, AnalyticsState.groups order unspecified, loading = lastSuccessAt == null with skeleton cards, offline looks like loaded (§13.3, §14.2.4). D-070: S-12 week title per strings.csv ("Vardag, vecka 41"), whole-range title ", ", no error state on S-11/S-12, no loading state on S-12 (§13.3). D-071: top-level screens S-3, S-4, S-11, S-13 render their own KvittNavigationBar with onNavigate, no second bar in :app; navigation-argument keys are feature constants read through SavedStateHandle; result snackbars shown by the screen returned to, account-archived snackbar with undo (§13.2). D-072: a new template's day of month defaults to today (AC-9.8, S-19). D-073: S-22 "Sök efter uppdatering" reports "Du har den senaste versionen" when UpdateState stays None; network failure indistinguishable, accepted for v1 (new AC-16.6, §14.2.4, §11.3). D-074: FieldError.field values are the model property names; an edited settlement keeps its saved rows, "Föreslå igen" re-proposes; S-9's untouched-accounts line derives from Home balances (AC-11.6, §13.3, §14.2.4). D-075: the D-060 fill is :core:design's quickRowCategories, replacing design-spec §3.7's interim rule (§14.2.4). D-076: category labels up to two centred lines, long custom names end in "…" (§13.3 S-7). D-077: day ranges in captions and summaries written out with the year, chip and S-12 title keep the short form (§9.8). D-078: stored amounts open for editing with both decimals, ratio percents trimmed (§9.6). D-079: shared keys common_ok, common_undo, editor_split_full_on_you and the M7b–M7f module keys recorded in strings.csv (578 rows, header included) (§13.4). D-080: "Synka nu" on S-8, S-10 and S-16 is online only; discard dialogs of S-6, S-7, S-9, S-19 have no body text (§9.9, §13.3). Without a decision id: §6.2 :app Hilt wiring before M8 (release binds :data since 6453932, the debug fakes module a41f240 is deleted by M8) and feature screenshot tests full screen at 411 × 891 dp xhdpi; §13.3 S-1 generic help line, S-2 blank-name error, S-3 error state, S-5 non-sticky month headers and "60/40" ratios (common_ratio), S-16 pending rows use the shared ledger rows, "Senare" hides the update banner for the ViewModel's lifetime; §11.3 contract requests for a later contract pass (M12e). §11: M7a–M7f and M6b landed, M8 and M7g started 2026-10-18 (M8 holds D-085 to D-089, renumbered to D-081 onwards on landing); §14.7 owners after landing. 0.12 2026-10-18 Outcome of M8 app integration (cb832a7 and 3d9eea8, gate green: BUILD SUCCESSFUL, 710 actionable tasks). D-081: both variants bind :data through di/AppDataModule.kt in src/main (includes DataBindingsModule); DebugFakesModule deleted; fakes only in tests and feature previews; :app tests on a plain Application; revises D-041 (§6.2, §11.3). D-082: a network security config cannot express IP ranges, so the debug config allows cleartext everywhere and SessionRepositoryImpl.normaliseServerUrl enforces the AC-2.8 limit; release config in src/main, debug override in src/debug, pinned-root config in src/releasePinnedRoot/res behind kvitt.tls.pinnedRoot; the debug InsecureBaseConfiguration lint warning is intended (§8.5, §10.5.3, AC-2.8). D-083: FCM registration by Firebase Installation ID (firebase-messaging 26.0.0, BoM 35.0.2, google-services 4.5.0): register() while paired and at each start, onRegistered(fid) sends fcm_token through E-17, unregister() on revoke, firebase_messaging_installation_id_enabled meta-data; no server change, fid field as a follow-up request (AC-13.7, §6.2, §14.6). D-084: an invite link opened while paired is ignored, never re-pairs (AC-2.6). D-085: a tap on the generic notification, a deletion or sync_batch opens Home; unknown type or v ≠ 1 only syncs; channel activity, notification id = hash of entity_id, sync_batch id 1; push handled by an expedited WorkManager job calling syncForPush (20 s) then building the text from Room (AC-13.6, §14.6). Without a decision id: the session gate (S-1, S-2, S-18; S-3 while partner == null) in §13.2; M8's :app wiring facts (LocalKvittHousehold, LocalKvittClock, LocalAvatarPictures, permission after the first sync, sync and update triggers, unsigned release without keys, exported components) in §11.2, §11.3, §8.8, §10.6, AC-2.9; M8's contract requests on the §11.3 M12e list (PushEvent to :core:model, S-22 licences, detail-screen snackbar hosts, S-7/S-8 snackbar strings, launcher icon, fid); new OQ-5 (licences screen, default not in v1). §11: M8 and M7g (3dda414) landed; M12e started 2026-10-18. The end-to-end pairing, offline and push test and the design-spec §2.7 typeface check on the phone are still to run. 0.13 2026-10-18 Outcome of the M12e contract pass (8c60715 contract pass, b7b7483 launcher icon; gates green: Android BUILD SUCCESSFUL, 710 actionable tasks, 906 tests; server 253 tests with the OpenAPI equality, vector and migration byte-identity tests). D-086: E-3 returns invite_kind; SessionRepository.pair returns OnlineResult<Pairing(user, inviteKind)>, an unknown kind reads as device; S-2 follows only a partner pairing; FakeScenario.pairingInviteKind (AC-2.4, AC-2.10, §13.2, §13.3 S-2, §14.2.4, E-3). D-087: E-12 link <public_url>/i/<code>?from=<admin name>; E-4 takes optional from and passes it only into kvitt://invite?server&code&from, never shown, an invalid value dropped; InviteLink, AppLink.Invite, PairingScreen(initialAdminName), PairingViewModel.prefill carry it; S-1 shows onboarding_code_help with the name; links without a name still parse (AC-2.5, AC-2.6, §13.3 S-1, E-4, E-12). D-088: SyncSummary.lastAttemptFailed; SyncStatusPill, syncPillVariant, syncLineText drop failed; S-16 failed = online and lastAttemptFailed (§13.3 S-4, S-16, §14.2.4, §11.3). D-089: Rejection.actor from the stored current.updated_by_user_id, partner as fallback; no protocol change (§14.2.4, §14.4.6). D-090: optional request header X-Kvitt-App-Version-Name on every operation, stored at E-3 and the hourly last-seen update, blank or over 32 characters ignored; migration 0003 adds devices.app_version_name, server schema 3 (new §14.1.2, contract copy with byte-identity test, v2→v3 migration test); app_version_name on the Device wire object; Device.appVersionName; S-20 shows "Kvitt 1.1"; importer expects schema 3; Room unchanged at 1 (§8.2, §10, §10.8, §14.1, §14.3.1, §14.3.3, E-1, E-3, AC-3.1, §13.3 S-20). D-091: RecurringRepository.create(NewRecurringTemplate), the server mints the id (§13.3 S-19, §14.2.4, E-28). D-092: UpdateRepository.check(): UpdateCheck (UpToDate, Available, Failed), 404 is up to date, debug reports UpToDate; S-22 up-to-date or could-not-reach-server; revises D-073 (AC-16.6, §13.3 S-22, §14.2.4). D-093: SettleState.untouched with nets excluding the edited settlement, empty per account; revises D-074's S-9 reading (§13.3 S-9, §14.2.4). D-094: the D-027 re-stamp as implemented: at the start of a cycle with clock_skew set, pending rows stamped later than now are re-stamped to now (§14.4.5). D-095: PushEvent in :core:model; six screens host the shared snackbar host, no :app overlay host; snackbar resource ids from S-7 and S-8; adaptive vector launcher icon (#9C5238, receipt_long at 48 dp, monochrome layer); revises D-071 (§6.2, §13.2, §13.3 S-7, S-8, §14.2.4, §14.6). Without a decision id: the 128 px picture size left unchanged by assumption (owner question open); the M12e list in §11.3 replaced by its outcome and a "Remaining contract requests" list (OQ-5 licences, fid); goldens re-recorded (S-20 devices; new s1_pairing_link_admin, s22_about_check_failed); compatibility note: the M12e APK needs a schema-3 server, so the server is redeployed first (§14.8); dev stack at schema 3, up.sh --down then up.sh on Podman (§10). §11: M12e landed (§11.1, §11.2). 0.14 2026-10-18 Follow-ups after M12e (a312758, f56dcbe, 3e6c337). D-096: the server sends the stored fcm_token (the Firebase Installation ID of D-083) in FCM HTTP v1 message.fid, no longer in the deprecated message.token; no database or wire change, the column and the E-17 field keep the name fcm_token; contracts/examples/push/*.json use fid; revises D-083's "no server change" (§14.6, AC-13.7, §11.3). Without a decision id: the Pi image's C stage and CA roots and an OAuth plus FCM call from the arm64 image confirmed on the Mac (docs/spikes/pi-image-arm64.md; 63.8 MB, cold build 48 s), running on the Pi stays M2c-pi's (§10.3); Vico removed from the version catalog (a312758), D-063 pointer (§6.2); §11.3 remaining contract requests: only OQ-5. 0.15 2026-10-18 The first phone test, M8b (328c466) and owner answers. D-097: chart bars top corners 4 dp, bottom 2 dp, replacing 10/4 (§6.2, §13.4, design-spec §2.9, §3.10). D-100: no SSH from the Mac to the Pis; M2c-pi delivers the infra/pi/ bundle the owner copies to the Kvitt Pi and runs, OQ-3 values as .env placeholders, M2c-pi last after the app is proven, no agent allowances on the Pis, Home Assistant, Gitea or Drive; revises D-023, keeps D-001 (§10 intro, §10.1, §10.10, §11.1, §11.2, §11.3, §12). D-101: the release keystore kvitt-release.jks at the repository root, git-ignored by *.jks, absolute path in android/local.properties, copy and password in the owner's password manager; revises D-024 (§10.6, §11.2 M10, §11.3). Without a decision id: the M8 end-to-end test passed on the owner's S26 against the development server (pairing, scripted partner via a second admin device, offline pending and sync, fcm_token and app_version_name registered, push by fid delivered and tapped); M8b fixes (invite-code VisualTransformation, quick-row badge above the ripple clip, KvittTopAppBar status-bar inset, 221 goldens) and FcmMessageBody.fid (6eb3f85) (§11.2 M8, §11.3); OQ-5 answered: licences button hidden in v1 (M8c); the 128 px picture size not needed (§14.2.4); the "boende" keyword keeps suggesting travel and the account page split bar stays as designed (no change). 0.16 2026-10-18 M8c (75b549f, a0c25b0, 7c453d8), the R8 release build (c30a49e) and M8d (bacbd18). D-098: goldens in three variants <name>_sv_light, <name>_sv_dark, <name>_en_light plus <name>_sv_light_200, rendered at 1x through w411dp-h<height>dp-mdpi, every committed PNG compressed with oxipng -o 4 --strip safe (1143 PNGs / 131 MB to 865 / 26 MB, mock-ups 36.8 to 26.0 MB); revises D-066 (§6.2, §13.4). D-099: S-22 has no open-source licences row, onOpenLicences and settings_about_licences removed, strings.csv 577 rows; closes OQ-5 (§11.3, §12, §13.3, §13.4, design-spec S-22). D-102: S-7 options as four fixed full-width rows (Konto, Datum, Betalt av, Delning), EditorOptionRows in :core:design; connected buttons 8 dp side padding (§13.3, §13.4, design-spec §3.7, §3.10). Without a decision id: release builds R8-shrunk, optimised and obfuscated, APK about 11 MB (was 43 MB), mapping.txt kept beside the APK; release signing verified (alias kvitt, RSA 4096, v2) (§10.6); §11.1 graph. 0.17 2026-10-18 The M2c-pi bundle (2476667), M8e (a59abeb), M8f (956908a), the chips cleanup (1328afe) and the Dockerfile CARGO_BUILD_JOBS argument (b4d9467). D-103: the infra/pi/ bundle (compose.yaml, was infra/compose.yaml; .env.example, was infra/env.example; Caddyfile; install.sh, deploy.sh <tag> [--skip-backup] with a backup before every deploy and /opt/kvitt/previous-tag, bootstrap.sh, backup-now.sh, install-apk.sh), the APK path infra/publish-apk.sh → infra/pi/out/apk/ → /opt/kvitt/apk/ → install-apk.sh into the data volume, mappings outside the volume, .env keys KVITT_REGISTRY_USER, KVITT_REGISTRY_TOKEN, KVITT_PI_HOST, KVITT_PI_SSH_USER, gate docker compose -f infra/pi/compose.yaml config; fulfils D-100 (§10 intro, §10.2, §10.3, §10.6, §10.7, §10.10, §11.2, §14.7). D-104: images `${KVITT_REGISTRY}/kvitt-server 0.18 2026-10-18 M12f (dc7a296, 5b2ed37, 2bd6b58, c366fbd, a0259ab), the server gap pass (8660b7f), the server overhaul (8103dae to b985ce9), the infra overhaul (2fac1ec to e70fe0d) and infra security fixes (7fb86f5), the AC-coverage audit and the security review. D-109: S-16 shows a rejected change's lost version read-only, Rejection.lost: RejectedVersion? with RejectedVersion(row, accountName, payer, mode, shares, notes, deleted) from rejected_payload, null when undecodable or a user or the category is missing; dialog "Din version", "Du tog bort den här", "Visa nuvarande version"; ledger rows take a null onClick (read-only); four home_sync_lost_* strings (§13.3 S-16, §14.2.4, §14.4.6, design-spec S-16). D-110: AboutState.schemaVersion; S-22 reads /health when it opens online and shows " (schema )" (settings_about_server_version_schema), header fallback offline (§13.3 S-22, §14.2.4, E-1, design-spec S-22). D-111: SettlementRepository.start and recompute return SettleState? (null without a session or partner), save returns Invalid(payer, validation_failed); no throws (§14.2.4, AC-5.1). D-112: a failed E-17 send is retried after each successful sync until accepted, a newer FID replaces it (AC-13.7). D-113: kvitt-server invite-partner (0 ok, 2 household full, 3 no admin) and the push sent info line (§8.7, §10.4); tools/contracts-check.py 134 checks. D-116: notifications VISIBILITY_PRIVATE with the generic public version (new AC-13.9); L-6 kept as built, S-1's server row expanded for a non-default server, the confirm step listed as OQ-6 (AC-2.6, AC-2.8, §12). D-117: Caddy log redaction of /i/<code> and query strings, Content-Security-Policy, X-Content-Type-Options, X-Frame-Options, Referrer-Policy (§8.7, §10.5.2, which now quotes infra/pi/Caddyfile at 7fb86f5); Caddy as uid 10002 with group 1000, read-only, cap_drop ALL plus NET_BIND_SERVICE, tmpfs; /certs 0750 1000:1000, caddy_data 10002, extending D-105 (§8.9, §10.2); the development stack copies only fcm-service-account.json into infra/dev/secrets/ (§10 intro); /opt/kvitt/deployed-digests with a WARNING on a changed digest and a workflow digest step; kvitt_cicd with write:package only (§10.3, §10.10); the plain root key (variant B) removed (§10.5.1); the remote_ip check (§10.10). D-114: pictures at most 16 000 000 pixels and 64 MB decoded, image_invalid (AC-4.4); fcm_token 1 to 512 characters, else invalid_request (§9.6, E-17). D-115: a token is accepted only after a 2xx, an unaccepted token counts against its IP, a 401 withdraws acceptance, entries pruned when their window expires; revises D-032 (§8.6). Without a decision id: the server overhaul (8103dae to b985ce9: shared row reads and inserts, invite creation and CLI helpers, one test harness tests/common/, clippy pedantic wins, synchronous tasks::start, not_implemented no longer produced; 268 server tests; all crates at their latest versions) (§6.3, §14.3.2, §14.7). Without a decision id: install.sh keeps the deployed KVITT_TAG, --provenance=false, the shared tools/gradle-lock.sh, RCLONE_REMOTE dropped from the development env (§10 intro, §10.3, §11.3); strings.csv 577 to 562 rows (§13.4); localeFilters en, sv (AC-19.1); work-testing and the screenshot harness fix (§6.2); release APK 10.0 MB (§10.6, §10.10); M12f row in §11.2 (941 tests); §11.4 validation reports (docs/validation/ac-coverage.md, docs/validation/security-review.md); the history rewrite and first push to origin (18c527f): every commit hash cited in this file is the rewritten one; 7c453d8 (the oxipng pass) no longer exists as a commit, its PNGs are in 18c527f. 0.19 2026-10-18 The Android overhaul (e4e6e5d to c582363). D-118: shared test support in :core:design's test fixtures (se.hagstedt.kvitt.design.testing: Variant, TestClock, TestEnvironment, ScreenSnapshots with Root/Screen/ScreenWhenIdle, MainDispatcherRule, withMain) through testImplementation(testFixtures(project(":core:design"))), not a module, the architecture check rejects test fixtures outside test configurations; the convention plugin kvitt.android.screenshots; format/Failures.kt, format/Limits.kt and savedSplitLabel in :core:design; KvittMotion only the seesaw spring, KvittIcon.Description and unused dimens and shapes removed; four catalog entries removed; one CopyCategoryKeywords task (§6.2 :core:design row and Screenshot tests, §11.1, §11.3; design-spec §2.11 and the icon table). Without a decision id: overhaul outcomes in §11.3 (Android c582363, server b985ce9, infra e70fe0d); 941 tests, no golden changed, release APK 10.46 MB; pushed to origin at c582363; infra/README.md APK size about 10 MB; pre-rewrite hashes in PLAN-*.md replaced by the rewritten ones. 0.20 2026-10-19 APK download rate limit (96e4cbd) and owner answers to the security review. D-119: E-6 GET /apk/files/{file_name} at most 10 requests per minute per client IP in its own fixed window, not counted against the 60 per minute of the other unauthenticated endpoints, every request counted (a 404 included), 429 rate_limited with Retry-After, client IP as in D-032, in memory; E-5 and E-4 stay on the 60 (§8.6, §10.6, E-6). Without a decision id: security review M-1 closed by the owner (backups stay unencrypted, rclone keeps the drive scope; accepted risk in §8.1 and §8.7); L-3 fixed; the D-114 limits (16 megapixels, 512-character fcm_token) confirmed by the owner (§11.4). 0.21 2026-10-19 The NPM rework (4f69ae0, d05f13a, 62f5279, 9231a1d) and the Android host property (d090c6c). D-120: TLS terminates in the owner's Nginx Proxy Manager on the Home Assistant Pi instead of Caddy and cert-sync, which are removed (infra/cert-sync/**, infra/pi/Caddyfile, images, volumes certs and caddy_data, secrets ha_ssh_key and ha_known_hosts, .env keys HA_PORT, HA_USER, HA_CERT_DIR); Kvitt gets its own host name KVITT_PUBLIC_HOST (owner-chosen, recorded in HANDOFF), KVITT_PUBLIC_URL=https://${KVITT_PUBLIC_HOST}:8443; router 8443 → NPM 443, nothing forwarded to the Kvitt Pi; the server publishes 8080 on the LAN, KVITT_TRUSTED_PROXY=${HA_HOST}; the NPM proxy host and its Custom Nginx Configuration carry over D-117's headers and log redaction (§10.5 rewritten: 10.5.1 Nginx Proxy Manager, 10.5.2 Custom Nginx Configuration, 10.5.3 Fallback: NPM down); health checks on 8080 and through NPM; the Gitea login interpolates the secret in the run line (reverses L-8's fix) (§1, AC-1.1, §6.1, §7, §8.5, §8.7, §8.9, §10 intro, §10.1 to §10.5, §10.7, §10.10, §11.2, §11.3, §11.4, OQ-3, OQ-6, E-7, §14.7). D-121 (d090c6c): the Android app's public host is the build property kvitt.publicHost (Gradle property, else android/local.properties, else the placeholder kvitt.example.invalid), exposed as BuildConfig.PUBLIC_HOST, the manifest placeholder publicHost and RELEASE_SERVER_URL = https://<host>:8443, injected into :feature:onboarding as @ReleaseServerUrl (AC-2.6, AC-2.7, §8.5, §10.5.3, §10.6, §13.3 S-1, OQ-6). Without a decision id: cargo audit in the server gate (f1abb0d). 0.22 2026-10-19 The D-121 follow-ups (4a4e45f, 4b1ae0c), the server's host defaults (c9abd24, e381e37) and the install.sh step number (ac17b41, no decision). D-122 (4a4e45f, 4b1ae0c; extends D-121): AppBuildInfo (defined in :data's DataModule.kt, provided by :app's AppBuildInfoModule) gains releaseServerUrl = RELEASE_SERVER_URL; S-22 shows the paired server, before pairing AppBuildInfo.releaseServerUrl; DataModule.DEFAULT_SERVER_URL removed; fakes and tests on https://kvitt.example.org:8443 (30 S-21/S-22 goldens re-recorded); infra/publish-apk.sh reads KVITT_PUBLIC_HOST from infra/pi/.env and passes -Pkvitt.publicHost (§6.2, §10.6, §13.3 S-22, §14.2.4). D-123 (c9abd24, e381e37; revises D-120's leftovers): KVITT_PUBLIC_URL has no default and every kvitt-server command refuses to start without it; KVITT_TRUSTED_PROXY defaults to none, never looked up; the OpenAPI server is https://{host}:8443 with variable host (default kvitt.example.invalid), representational for §14.8; E-7 and E-12 examples on kvitt.example.invalid; tools/contracts-check.py expects the {host} URL; 276 server tests (§10.4, §11.3, §14.3, E-7, E-12). The owner's Kvitt host name kvitt.suorra.duckdns.org (2026-10-19, recorded in HANDOFF; §10.1, §10.5, §10.5.1). 0.23 2026-10-19 Port 443 (a86ad24 server and contracts, 4852803 bundle, 038c603 Android, ad35231 portless Android fixtures, 30 S-21/S-22 goldens re-recorded) and the pinned-root template (038c603, no decision). D-124 (owner decision 2026-10-19): Kvitt is served on port 443 (https://<host>, no explicit port) because NPM listens on 443 and selects by host name; the router's existing external-443 forward to the Home Assistant Pi serves Kvitt, no 8443 rule. Server and contracts: OpenAPI server https://{host}; E-7 and E-12 examples without a port; tools/contracts-check.py expects the portless header. Bundle: KVITT_PUBLIC_URL=https://${KVITT_PUBLIC_HOST}; health checks through NPM on 443; README router step "no new rule"; the APK-abuse stop-gap is disabling Kvitt's proxy host in NPM. Android: releaseServerUrl(host) = https://<host> (RELEASE_SERVER_PORT removed); the AC-2.6 intent filter has no port and matches every port of the host, so an old :8443 link still opens S-1 with the server it names; invite-link parsing drops an explicit default port (:443, :80); S-1 goldens on https://kvitt.example.org (28 re-recorded) (§1, AC-1.1, AC-2.6, §6.1, §7, §8.1, §8.5, §10.1, §10.2, §10.4, §10.5, §10.5.3, §10.6, §10.10, §11.2, §11.3, §11.4, §14.2.4, §14.3, E-7, E-12). Without a decision id: the pinned-root config is generated at build time from the template android/app/src/releasePinnedRoot/network_security_config.xml with the domain kvitt.publicHost, only when kvitt.tls.pinnedRoot=true, and the build stops while android/app/src/release/res/raw/kvitt_root_ca.crt is not committed (§8.5, §10.5.3). 0.24 2026-10-20 The self-contained Pi compose project (6e5981d), the .env without informational keys (200c99f) and the sparse-checkout workflow (3820f9c, no decision), with the workflow's first results; the compose deploy hint in the workflow and infra/build-images.sh (28fa71b, no decision). D-125 (owner decision 2026-10-20, revises D-103, D-105, D-117 point 5, D-120 point 6): the Kvitt Pi runs Kvitt from /home/jacobhagstedt/kvitt, a self-contained compose project (compose.yaml, .env, secrets/, relative bind mounts ./data, ./backups, ./import); both containers run as the owner's uid/gid (KVITT_UID/KVITT_GID, 1000 on the Pi) with a read-only root and a 16 MB tmpfs /tmp, backup HOME=/tmp; each mounts only its own secret file read-only (create_host_path: false), secret files the owner's, mode 0600; .env holds exactly the seven keys compose reads, RCLONE_REMOTE fixed to gdrive:; no install script, no /opt, no Docker daemon or system changes (Docker and the registry trust are prerequisites; private packages mean a one-time docker login gitea.lan); the scripts install.sh, deploy.sh, bootstrap.sh, backup-now.sh, install-apk.sh, lib.sh removed, their equivalents plain docker compose commands (backup exec backup /backup.sh, bootstrap and partner invite through exec server kvitt-server, deploy = backup, set KVITT_TAG, pull, up -d, rollback = the previous tag, APK = scp of the APK and then latest.json into data/apk/, old APKs removed by hand, digests with docker image inspect, no digest record, health checks by hand); restore moves files on the host, only rclone and sqlite3 run in the backup container; the compose default network; the development stack unchanged (uid 10001); rehearsed with Podman as uid 501 (§8.5, §8.9, §10 intro, §10.1, §10.2, §10.3, §10.4, §10.5, §10.5.1, §10.6, §10.7, §10.8, §10.9, §10.10, §11.2, §11.3, §12 OQ-3, §14.7). Without a decision id: the .env keys KVITT_PI_HOST and KVITT_PI_SSH_USER dropped (200c99f, revises D-103), <KVITT_PI_HOST> is now <kvitt-pi-address> (§8.9, §10.1, §10.5.1, §10.5.3, OQ-3); the Gitea workflow's results on the owner's Pi runner (act_runner 0.6.1, Alpine job container): the first failures were an empty secret (a misnamed user-level secret, fixed by the owner 2026-10-19), run 69 built v1.0.0 (kvitt-backup 5 min 20 s, kvitt-server 2 h 42 min, first build with CARGO_BUILD_JOBS=1), the sparse-checkout push built v1.0.1, the tag the Pi uses; the checkout is a cone-mode sparse checkout of server and infra/backup with fetch-depth: 0 and --filter=blob:none; the diagnostic step removed (§10.3, §11.2). 0.25 2026-10-21 The app gate (D-126, owner decision 2026-10-21; Android 34e5cad): outside the home LAN 192.168.1.0/24 NPM closes the connection (return 444) of every request without X-Kvitt-App: <key>, every route included (/health, /setup/status, /invites/accept, /i/{code}, /apk/*); only /.well-known/acme-challenge/ passes (Let's Encrypt renewal), tested on $uri; the LAN check reads $realip_remote_addr, because NPM's real_ip_header X-Real-IP for private peers makes $remote_addr forgeable; the server and contracts/openapi.yaml are unchanged, the bearer token stays the authentication. The app sends the header in KvittApi's common headers and PictureAuth when built with kvitt.appKey (Gradle property, else android/local.properties, else empty = no header; 16 to 128 printable ASCII characters without white space; BuildConfig.APP_KEY, AppBuildInfo.appKey; 952 Android tests); the key is the owner's openssl rand -hex 32, only in local.properties and NPM; rotation by a second if line, a new APK through FR-16, then the old line removed. Accepted: landing page and browser use only on the LAN, outside health check through the app's About screen or curl -H, a leaked APK leaks the key until rotation, no flood protection. The gate rehearsed in NPM v2.16.0's openresty with its includes (AC-2.5, §8.1, §8.5, §10.1, §10.5, §10.5.1, §10.5.2, §10.6, §10.10, §14.3.1). Without a decision id: infra/README.md step 4a (key, APK, gate, acceptance test), its CARGO_BUILD_JOBS text (in effect since b4d9467; run 69: kvitt-server 2 h 42 min) and its owner decisions marked answered. 0.26 2026-10-21 Pull-to-refresh on Home and account detail (D-127, owner request 2026-10-21; Android 3778f5f; revises design-spec S-4 "Pull-to-refresh is not offered"): pulling S-4 or S-5 past the threshold runs SyncRepository.syncNow(), the call behind S-16 "Synka nu"; the indicator stays while the sync runs and goes when it returns, success or failure; a failure shows only in the sync pill (S-5 has none, so a failed pull there shows nothing until Home's pill); offline the pull ends at once without a sync; a pull while a sync runs starts no second one. Shared KvittPullToRefresh in :core:design (component/Refresh.kt): Material 3 PullToRefreshBox with a Kvitt indicator (48 dp primary-container disc, the sync icon 18 dp turning 270° with the pull and popping from 80 % at the threshold on the new KvittMotion.spatialFast() with a GestureThresholdActivate haptic, a 32 dp primary arc that fills to the threshold and turns indeterminate while refreshing); ContainedLoadingIndicator replaces the arc once the pinned Material 3 (1.4.0) ships it. TalkBack reads "Synkar…" (sync_syncing, reused) as a polite live region; S-16 stays the TalkBack path. New goldens S-4-home-refreshing and S-5-account-refreshing; 959 Android tests. No change to :core:model, Room, the sync protocol, the server or docs/ux/strings.csv (AC-15.3, §9.9, §13.3; design-spec §2.11, §3.1, §3.6, S-4, S-5). 0.27 2026-10-21 S-12 line chart for a category or account over the range (D-128, owner request 2026-10-21; Android 12e2508). S-12 opened from a breakdown row shows its own period chip (AC-14.2 presets plus custom) and Month/Week toggle, both starting from S-11's values and changing chart, total and list on S-12 only (S-11 keeps its state; measure and group-by come from S-11 and are fixed on S-12), the header total, the "Utgifter över tid" card and the expense rows; a drill-down from a bar is unchanged. One point per bucket, empty buckets as zero (AC-14.7), from the group's bucket totals of spendSeries (§14.5.4); an empty range shows only the 0 baseline (D-068) and "Inga utgifter i den här perioden". Overlays: the range average (total ÷ buckets, half-up to öre) as a dashed line in the group colour with its amount at the right end; a trailing moving average over 3 buckets (AnalyticsRules.MOVING_AVERAGE_WINDOW; the first buckets use the 1 or 2 that exist) as a thinner neutral line; legend "Snitt", "Glidande snitt (3)"; caption ": N % över snittet" / "under snittet" / "på snittet" for the latest bucket the range does not cut short, N a whole percent half-up. Overlays and caption omitted when the average is 0 or the range has one bucket; caption omitted when no bucket is whole. Not interactive; one TalkBack summary. :core:design gains SpendLineChart and LineLegend (chart/LineChart.kt), axis code shared with StackedBarChart in Charts.kt; AnalyticsFilterBar measure and group-by toggles optional. Seven strings.csv keys (569 rows). New goldens s12_category_groceries, s12_category_week, s12_category_empty_range, line_chart, line_chart_variants; s12_category, s12_account, s12_long re-recorded; 977 Android tests. No change to :core:model, :domain, :core:fakes, Room, the server or the contracts (new AC-14.11; §13.3 S-12, §13.4; design-spec §3.10, S-12). 0.28 2026-10-21 The web client programme (owner interview 2026-10-21; no implementation yet; v0.27 is D-128's). D-129: a web client with the Android app's features except the phone-only ones (pairing flow, push, offline, in-app update), plus free-text search, CSV export of the filtered list, keyboard shortcuts N, /, Esc, ? and a language choice; desktop first, one column under 720 px, sv and en, not a PWA (§1, §2 revised, new §15, FR-21). D-130: the browser logs in with an invite code through E-3 as device Web · <browser>, token in localStorage, revocable on Devices; the NPM gate also passes /app and /app/…, POST /invites/accept and bearer-token requests except /health, /setup/, /i/ and /apk/ (§8.5, §10.5, §10.5.2, infra/README.md steps 4 and 4a, infra/npm/kvitt.conf; checked with nginx 1.31.7, 17 requests). D-131: web/ stack (Vite, React 19, TypeScript strict, React Router 7, TanStack Query 5, openapi-typescript and openapi-fetch, Recharts, Vitest, ESLint, Prettier, CSS modules with design-spec tokens, JSON dictionaries), the money functions passing the vectors, the web gate npm run check (§11, §15.3). D-132: the web client is built by a Node stage of server/Dockerfile (context the repository root) and served by kvitt-server under /app/ from KVITT_WEB_DIR with an SPA fallback; immutable hashed assets, no-store index.html; the /app/ CSP through $kvitt_csp in NPM (§10.3, §10.5.2, §10.6, §15.4). D-133: advanced analytics on the server under /analytics/* (per-category averages and trends, a two-month forecast per account = recurring templates due + the 3-month average of non-recurring spend), for the web and the app; AC-14.1 and G-5 revised (§15.8; endpoints D-135 to D-138, v0.29). D-134: plans W0 to W7 with disjoint paths (§11.1, §11.2, §11.3, §14.7, §15.9; PLAN-W0.md to PLAN-W7.md, prompts/W0.md to prompts/W7.md). The change log becomes §16. 0.29 2026-10-21 The server side of the web client programme (W7, 50a0d67) and the unattended APK deploy (70cb25c). D-135 web serving: KVITT_WEB_DIR (default /app); GET /app → 308 /app/; files from the directory, every other path index.html, a missing assets/* 404; assets/* public, max-age=31536000, immutable, index.html no-store, others no-cache; the $kvitt_csp web policy plus nosniff, DENY, no-referrer; safe paths at most 512 bytes and 8 segments of [A-Za-z0-9._-] not starting with .; no directory → /app 404 (§10.4, §15.4, AC-21.1). D-136: /app, /app/, /app/* count against the unauthenticated 60/min per IP, bearer token or not (§8.6). D-137 image build: repository-root context with an allowlist .dockerignore (server, web, contracts), server/.dockerignore removed; a Node node:24.22.1-bookworm-slim stage pinned by digest on the build platform, its dist passed through the Rust stage so npm and rustc never run together on the Pi 3; workflow context ., sparse checkout and path filter add web and contracts; infra/build-images.sh and infra/dev/build.sh follow; Cargo.lock bumps rustls-webpki 0.103.16 and webpki-root-certs 1.0.10 (RUSTSEC-2026-0382, -0383) (§10.3). D-138 analytics: E-34 GET /analytics/trends and E-35 GET /analytics/forecast, authenticated, read-only, with examples; rules in new §14.5.7 (kvitt-domain::analytics) (§7, §14.3.4, §14.3.5, AC-14.1, §15.8). D-139 (70cb25c): infra/publish-apk.sh --deploy copies the APK and latest.json with a forced-command key and checks /apk/latest (§10.6). Server tests 299; contracts-check 136. 0.30 2026-10-21 The manual update check (c0f4345). D-140 (owner, 2026-10-21): S-22 "Check for update" shared the throttled automatic check, so a tap within 6 hours of the last automatic check reported the stored answer (the owner deployed a new APK and was told "You have the latest version"); UpdateRepository.checkNow() (default implementation calls check(), so fakes are unchanged) always asks the server and restarts the 6-hour window, debug builds still return UpToDate without a request; AboutViewModel.check() calls checkNow(); the automatic checks on cold start and resume keep the throttle (AC-16.2, AC-16.6, §13.3 S-22, §14.2.4). 0.31 2026-10-21 Android Insights on S-11 (W6, 1c9856b; Android gate green, which also fixes the E-34/E-35 example tests red since 50a0d67). D-141 UI contract: :core:model InsightsRepository with trends(months: 1..24, measure) and forecast(measure), both OnlineResult (Offline without a request, Failed("network") when unreachable); types SpendTrends, SpendTrend, TrendPoint, CategoryTrend (category: Category?), SpendForecast, AccountForecast (account: Account?), ForecastMonth, named after the E-34/E-35 fields; names resolved from Room, archived and deleted included, unknown id → null; nothing stored; :data AnalyticsDtos.kt, InsightsRepositoryImpl, two KvittApi calls; fakes FakeInsightsRepository, InsightsScenarios, insightsFailure (§14.2.4). D-142 placement and loading: an "Insights" ("Insikter") section below S-11's local analytics, following S-11's measure toggle, always 6 whole months (E-34's default); loads when S-11 opens, when the measure changes to one not yet loaded, when the phone comes online and on "Försök igen"; data kept in memory per measure while S-11 is open; the last data stays visible under the offline or error banner; S-11's offline analytics unchanged (AC-14.1) (§13.3 S-11, design-spec S-11). D-143 display rules: the household chart and a per-category chart on D-128's SpendLineChart with the server's average and moving average; categories in the server's order, the open one defaults to the largest total; unknown category ids skipped; one forecast card per account (archived badge) with the current month so far and two months as "Recurring + average = forecast"; an all-zero card shows one line "No recurring expenses and no recent spending" (design-spec S-11, §3.10). strings.csv 588 rows (16 analytics_insights_* keys, 19 rows) (§13.4). Goldens s11_insights_<state> for 13 states in three variants plus s11_insights_long_sv_light_200. 0.32 2026-10-21 The web feature plans W1 to W5 (934eee7, a65ab71, f9a9bfb, 1aecf51, 3ebe57d; web gate on main 59 files, 532 tests at 1aecf51, 598 at 83f5293 with the suggest_category vectors) and the update install-failure fix (d686ee0). D-144: the preset account travels as ?account=<id> for /app/expenses/new and /app/settle, a payment being edited as /app/settle?settlement=<id>; builders in features/accounts/links.ts and features/settle/links.ts until W0 adds them to routes.ts. D-145: web Home's empty state shows the "Du och är med" card in place of the balance header; the archived section's open state lasts for the page session in memory. D-146: CSV export format (UTF-8 with BOM, ;, CRLF, RFC 4180 quoting, "1234,50" in every language, ISO dates, header in the page language, one share column per user, formula cells prefixed ', kvitt-utgifter-<date>.csv / kvitt-expenses-<date>.csv). D-147: AC-8.6's "on this phone" is this browser (localStorage); search filters in the URL (amounts in öre). D-148: web expense editor: rejections and failures in a banner with S-16's text and "Visa nuvarande version", the server's row into the snapshot, typed values kept; "Utgiften sparades" after edits too; the discard dialog on Esc and in-app navigation; browser controls in place of S-7's keypad, ratio slider and summary row; shared fields in web/src/components/editor/; the keyword table imported raw (server.fs.allow). D-149: W-7 shows the §14.5.3 allocation errors as you type. D-150 unused. D-151: a bar opens /app/analytics/bucket/<key>; the filter in the query string (range, from, to, interval, measure, group, bucket), replaced by W-10's own period changes. D-152: chart SVGs hidden from screen readers, bar labels as keyboard stops, "Visa som tabell"; W-11 offers 3, 6 or 12 months. D-153: W-18's route is /app/settings/invite (/invites still opens it); W-15 and W-16 editor routes. D-154: the partner's first-login step is an intro on W-14 remembered in kvitt.profileStepDone (the device id); W-19's fallback reads the server-version header of a fresh GET /me (§15.3, §15.6, §15.7, AC-8.6). D-155 (d686ee0): a refused or failed install shows "Kunde inte installera uppdateringen" with the reason (blocked by the security settings, or the installer's message) and "Försök igen", which downloads again; a declined dialog returns to Available; UpdateState.Failed gains reason: UpdateFailure (Download, Blocked, Install(detail)) (new AC-16.7, §13.3 S-17, §14.2.4; design-spec §3.6, S-17, S-22). strings.csv 590 rows (update_install_failed, update_install_blocked). Goldens S-17-install-blocked, S-17-install-failed, s22_about_install_blocked new, update_banner re-recorded. contracts-check 136. 0.33 2026-10-24 Owner answers and phone observations of 2026-10-24 (D-156) and the small-edits working rule (D-157). D-156: OQ-6 answered, no confirm step on S-1 for an unusual server (§12); security review L-10 answered, a member naming the other user's device gets not_found (AC-3.2, §8.4, E-16; to implement, the server answers forbidden today); no host firewall rule limiting port 8080 to HA_HOST for now (§10.2, deferred); mem_limit kept and advisory on the Pi (§10.2); images keep being built on the Pi 3 runner until the current run's result, infra/build-images.sh the fallback, docker builder prune -af between builds (runner disk 11 of 15 GB, §10.3); Samsung Auto Blocker must be off for the in-app install (AC-16.3); AC-18.1 verified by the owner, AC-16.3 and the editor keyboard fix observed on the phones, both phones on release 140 (AC-18.1, §11.4); the web client is first used from the laptop browser (§15.2). D-157: small edits by a Haiku or Sonnet agent directly in the main checkout, committed on main by the orchestrator (working rule, CLAUDE.md). infra/README.md "Pi: what the owner does" gains the prune and Auto Blocker notes. contracts-check 136. 0.34 2026-10-24 L-10 implemented (07c36d2, D-156) and the web shared follow-ups (W0b, 5305f37), no new decision. L-10: a member naming the other user's device gets E-16's not_found, the same body as an unknown id; contracts/openapi.yaml drops E-16's 403 and web/src/api/schema.d.ts is regenerated (contract change, §14.8); the "to implement" notes of AC-3.2, E-16 (§14.3.4) and §11.4 removed; Cargo.lock bumps ctutils 0.4.3 → 0.4.4 (RUSTSEC-2026-0385, published 2026-10-23, which failed cargo audit on main). Server tests 300; contracts-check 136. W0b: shared web pieces once in components, lib, api and app, no feature imports another (catalog.test.ts also checks web_ keys); amount fields per page language; Recharts in its own chunk (vendor 516 → 132 kB); Vitest cache off; Testing Library's findBy/waitFor limit 5 s in web/src/test/setup.ts (load on the Mac during parallel agents); the version code from the commit count, else KVITT_VERSION_CODE, else 1 (§15.3). Web gate 609 tests. Image build: server/Dockerfile's Node stage takes ARG KVITT_VERSION_CODE=1 into npm run build, and the Gitea workflow passes --build-arg KVITT_VERSION_CODE=<git rev-list --count HEAD> (§10.3). 0.35 2026-10-24 Card purchases through Enable Banking (owner's request and answers of 2026-10-24, D-158 to D-176) and plans K0 to K3. D-158: card purchases in scope, §2's card and bank non-goal struck through with a pointer, new US-18, US-19, FR-22 (AC-22.1 to AC-22.15), §9.12 (CP-1 to CP-14). D-159: Enable Banking in restricted production for the SJ Prio Mastercard (SEB Kort), G-7 allows it, PSD2 limits stated as facts, ToS as the owner's licence step. D-160: server-only credentials, one adapter src/cards/enable_banking/, provider registry, card catalogue E-36. D-161: only the card holder sees their purchases (owner's answer): own endpoints and cursor, not in GET /sync, audit, push or analytics, not_found for the other user, no card content in logs, session id protected by separation from the private key (§8.1, §8.4, §8.7, §10.9). D-162: connect flow with single-use attempts (E-37, E-38), the callback E-39 and its bilingual page, kvitt://cards/connected, polling. D-163: /cards/callback through the app gate and never logged (§10.5.2 block). D-164: history 7/30/90/180 days, default 30. D-165: background fetches at 06:45, 11:45, 16:45, 21:45, at most 4 per 24 hours; user-present "Uppdatera" with Enable Banking's PSU headers, once per 60 s; incremental fetch with a 10-day overlap; card_bank_unavailable. D-166: consent up to 180 days, notice 14 days before, renewal with BankID; card_consent_expired. D-167: migration 0004, server schema 4 (card_sequence, card_connections, card_auth_attempts, card_purchases, §14.1.3); disconnect rules (E-43). D-168: transaction mapping, pending→booked de-duplication, foreign currency, credits listed only under "Alla". D-169: "Skapa utgift" prefill, links (E-44), offline-capable link changes, unlink on expense delete (§14.4.4), expense_already_linked. D-170: suggested matches (same amount, ±3 days), matchCardPurchase with vectors match_card_purchase.json (§14.5.8). D-171: no bulk add, no card push (OQ-7, OQ-8). D-172: four bottom destinations, Översikt, Kortköp, Statistik, Inställningar (revises D-048); "Anslut kort" in Settings. D-173: :feature:cards, S-23 to S-27, Room version 2, CardRepository (§14.2.4), the owner's SJ Prio artwork with a drawn fallback. D-174: web W-21 to W-23 (K3). D-175: KVITT_EB_* configuration, secrets/cards/, two optional .env keys; cards_unavailable. D-176: plans K0 (the local test app of 2ce317f, owner's refinement) to K3; K0's TODO(spec) answers go into v0.36 before K1. Endpoints E-36 to E-44; strings for the card screens and the callback page in §13.3; ownership rows K0 to K3 (§14.7); contract files 0004 and the new vector file (§14.8). 0.36 2026-10-24 K0's results (the spike run on the owner's SJ Prio Mastercard on 2026-10-24 with docs/spikes/k0/app.py, report docs/spikes/K0-enable-banking.md), D-177 to D-180; no contract file changes, server schema 4 and Room 2 as specified in v0.35. D-177: K0's outcome; every K0 TODO(spec) of §9.12 answered: ASPSP SJ Prio Mastercard, SE (CP-1); one CARD account per session (CP-2); at least 150 days of history right after BankID, so 7/30/90/180 stay (CP-3, §9.6); a background fetch without PSU headers accepted (CP-4); required_psu_headers [psu-ip-address], compared case-insensitively (CP-5); maximum_consent_validity 180 days, valid_until 2027-04-22 (CP-6); foreign purchases arrive in SEK (CP-7); credits were card-bill payments (CP-8); and the owner's assumptions of 2026-10-24 for what was not measured: the partner's card links to the owner's application (CP-13, the D-175 fallback stays), a pending transaction keeps its entry_reference when booked (CP-8, the amount-and-date rule becomes the secondary rule), the session is reused on later days without BankID (CP-6), all three verified by K1's owner steps. D-178: the card returns at most 100 transactions per response and never a continuation_key, so history is fetched in windows of at most 30 days, newest first, a window at 100 rows split in half down to one day, de-duplicated across windows by provider_ref; strategy=longest dropped; WRONG_TRANSACTIONS_PERIOD ends the walk back; only a complete fetch deletes vanished pending purchases (CP-7, CP-8); card_fetch counts requests, splits, truncated windows, booked_by_ref and booked_by_match (§8.7). D-179: transaction mapping from K0's field survey: merchant = remittance_information, else creditor.name, else "Kortköp"; purchase_date = booking_date, else value_date, else transaction_date; bank_transaction_code unused, so a debit FEE is a purchase to handle; the holder's name, the masked card number (CPAN) and the merchant's address are never stored, logged or shown (CP-7). D-180: the owner's SJ Prio Mastercard artwork cropped to the card (1313 × 829) and committed for Android and the web, mapped from the first commit of K2 and K3, the goldens use it, the owner's artwork steps removed (revises D-173, D-174). The K plans' proposed spec text goes into v0.37 (§11.1, §11.3). 0.37 2026-10-24 D-211: image builds on the Mac with Podman (infra/build-images.sh v1.0.N) are the normal path, the Gitea workflow on the Pi 3 runner the fallback (revises D-156 point 5); tag rule (the next v1.0.N after the highest tag on origin, pushed as a git tag too, v1.0.3 = 8fa9198); the registry from the Mac is gitea.lan on port 80, the Pi's .env keeps gitea.lan:3001; Podman's insecure-registry files on the Mac and in the Podman machine; the script fixes f15fa23 and 8fa9198 (§10.3, §10.10). v1.0.3 deployed on the Kvitt Pi and the web client and S-11's Insights verified by the owner (§11.2 W1 to W7, §11.3, §11.4, §15). No contract file changes. 0.38 2026-10-24 K1's report (card purchases on the server, landed 671c00d: migration 0004 byte-identical to §14.1.3, server schema 4 in code, E-36 to E-44 with four new error codes and a 502 BadGateway response in contracts/openapi.yaml, examples, match_card_purchase.json with its Python reference; gates at landing: server 356 tests, contracts-check 157, web 609, nginx check and compose configs ok, the Android gate red until K2 lands), D-181 to D-188 (D-189 and D-190 unused). D-181: the history counts today, date_from = today − (history_days − 1), 6 windows for 180 days (revises CP-3 and CP-7). D-182: the server's CS-4 first token for CP-8 uses Rust's standard Unicode classes without NFC. D-183: Enable Banking's errors mapped to CP-14 (EXPIRED_SESSION, CLOSED_SESSION, REVOKED_SESSION, SESSION_DOES_NOT_EXIST → consent_expired and expired; ASPSP_RATE_LIMIT_EXCEEDED or 429 → rate_limited; ASPSP_ERROR, ASPSP_TIMEOUT, 408, 5xx or no answer → bank_unavailable; anything else failed); E-37's card_bank_unavailable when /aspsps or /auth fails. D-184: the callback (an expired state stores expired, revising CP-2's failed; a used one changes nothing; neither code nor error → failed/bank_error; a session without accounts is revoked; the atomic claim). D-185: the poller's start-up slot, background starts counted whatever their outcome, deletion after WRONG_TRANSACTIONS_PERIOD only over the windows that answered, a split window's cut rows discarded. D-186: PSU headers only with a value, /aspsps cached 24 hours, the two fixed headers when it fails. D-187: E-41 with the current value and E-43 on a disconnected connection make no new version (erase_handled=true still erases), E-44's field for a credit purchase, CardAttempt.failure a plain nullable string. D-188: src/wire/card.rs, row helpers in src/cards/mod.rs, the client IP in a request extension, and the Pi's compose.yaml refusing to start until secrets/cards/ exists. Changed: §9.12 CP-2, CP-3, CP-4, CP-5, CP-7, CP-8, CP-14; §10.2; §11.1, §11.2 K1 row, §11.3 (K2's text goes into v0.39, K3's into v0.40); §14.1.3; §14.3.3; §14.3.4 E-1 (schema_version 4), E-37, E-39, E-41, E-43, E-44; §14.3.5; §14.7. 0.39 2026-10-24 K2's report (card purchases on Android, landed a8f91ee: Room version 2 with MIGRATION_1_2, its test and the exported 2.json; the CardRepository UI contract of §14.2.4 unchanged in its names; the card cycle; :feature:cards S-23 to S-27; S-5, S-7, S-8, S-13 and the fourth bottom destination; Android gate at landing BUILD SUCCESSFUL, 791 actionable tasks, 1154 tests, 0 failures, VectorFilesTest and ExampleRoundTripTest green again; 150 goldens added, 147 re-recorded for the bar), D-191 to D-200. D-191: the card cycle after each successful household cycle and after refresh, never changing the household outcome; E-40's 404 is "no card support", retried every cycle. D-192: E-44's expense_already_linked or validation_failed resets the row's card_version to 0 and moves the card cursor back before it (§14.2.1). D-193: links to expenses no longer on the phone cleared before E-44 and at every local delete or rejection that removes an expense. D-194: the E-36 catalogue cached in DataStore (card_providers, §14.2.2). D-195: after a connect or E-42's fetching, E-40 every 3 s, at most 40 times, until last_fetch_at or last_fetch_error changes. D-196: the return link held by AppViewModel: S-25 polls it at once, else one E-38 call and S-23. D-197: bottom-bar labels shrink to fit down to 70 % (design-spec §3.11). D-198: S-23's filter chips wrap; S-25's and S-26's history as wrapping chips (revises S-25's segmented choice). D-199: S-13 "Har upphört" for an expired connection; S-5's "Från kortköp" hidden on archived accounts. D-200: four added string keys and the card artwork measures in KvittDimens. §13.2 (the destination enum as built), §13.3 S-5, S-13, S-23 to S-27 as built and the added keys, §14.2.1 to §14.2.4 (Room 2 landed; readings fixed in v0.39), §11.2 K2 row, §11.3, new OQ-9 (CardPurchase.linked while the expense is missing, §12). docs/ux/design-spec.md: S-23 to S-27 sections from the goldens, §3.11 four destinations and shrink-to-fit, §3.12 card artwork, the credit_card icon, S-5, S-7, S-8, S-13 card states. No contract file changes in this pass (Room 2 is K2's). contracts-check 157. 0.40 2026-10-24 K3's report (card purchases on the web, landed faeb752; web gate at landing 70 files, 684 tests, build ok; contracts-check 157), D-201 to D-207 (D-208 to D-210 unused). Built: W-21 /app/cards (every §13.3 state but offline, the S-23 sheet actions, ?attempt= polling E-38 every 2 s, ?account= as S-27), W-22 /app/settings/cards (catalogue, connect step ?provider=), W-23 /app/settings/cards/:id (history, renew, disconnect with erase); W-5's ?cardPurchase= prefill (CP-9) and link on save; W-6's card line with "Ta bort koppling"; W-3's "Från kortköp"; W-13's "Anslut kort" row; Kortköp after Översikt in the sidebar and bottom bar; matchCardPurchase in web/src/lib/domain/ passing the 17 vectors (ported). Shared pieces outside PLAN-K3 §4, ratified at landing: web/src/api/cards.ts with its test, web/src/test/cards.ts, /cards in the dev proxy, the icons credit_card, link_off, visibility_off, Shell.test.tsx; a refresh of the card snapshot no longer re-reads the catalogue and attempt queries (shared key prefix, now exact). D-201: W-21 re-reads E-40 every 2 s while a connection is fetching or in its first fetch, otherwise every 60 s. D-202: query names cardPurchase (W-5), attempt (W-21), provider (W-22, S-25, also "Förnya med BankID"). D-203: only an https: auth_url is followed. D-204: the outcome after ?attempt= is dropped (snackbar "Kortet är anslutet"; a banner with "Försök igen" to W-22 ?provider=). D-205: W-5 for an unknown or deleted purchase, and a failed E-44 after save. D-206: valid_until in the detail date form (W-21 banner, W-22 tile, W-13 row), W-6's line in the list form. D-207: W-21 with ?account= is S-27 (title "Från kortköp", rows open W-5, no chips, no panel). Changed: §11.1, §11.2 K3 row, §11.3, §14.7 K3 row, §15 status, §15.3, §15.5 (the card snapshot), §15.6 W-5, W-6, W-13, W-21 to W-23 and the navigation paragraph, §15.9. No contract file changes.